CMP Journal 2025-08-06
Statistics
Nature: 23
Nature Physics: 1
Physical Review Letters: 12
arXiv: 44
Nature
Therapeutic genetic restoration through allogeneic brain microglia replacement
Original Paper | Haematopoietic stem cells | 2025-08-05 20:00 EDT
Marius Marc-Daniel Mader, Alexa Scavetti, Yongjin Yoo, Aaron Tianyue Chai, Takeshi Uenaka, Marius Wernig
Migration of transplanted allogeneic myeloid cells into the brain following systemic hematopoietic stem and progenitor cells transplantation (HCT) holds great promise as a therapeutic modality to correct genetic deficiencies in the brain such as lysosomal storage diseases.1-3 However, the toxic myeloablation required for allogeneic HCT can cause serious, life-threatening side effects limiting its applicability. Moreover, transplanted allogeneic myeloid cells are highly vulnerable to rejection even in an immune-privileged organ like the brain. Here we report a brain-restricted, high-efficiency microglia replacement approach without myeloablative preconditioning. Unlike previous assumptions, we found that hematopoietic stem cells are not required to repopulate the myeloid compartment of the brain environment. In contrast, Sca1- committed progenitor cells were highly efficient to replace microglia following intracerebral injection. This finding enabled the development of brain-restricted preconditioning and avoided long-term peripheral engraftment thus eliminating complications such as graft-vs-host disease. Evaluating its therapeutic potential, we found that our allogeneic microglia replacement method rescues the murine model of Sandhoff disease, a lysosomal storage disease caused by hexosaminidase B deficiency. In support of the translational relevance of this approach, we discovered that human induced pluripotent stem cell-derived myeloid progenitor cells display a similar engraftment potential following brain-restricted conditioning. Our results overcome current limitations of conventional HCT and may pave the way for the development of allogeneic microglial cell therapies for the brain.
Haematopoietic stem cells, Microglial cells, Neurodegeneration, Neuroimmunology, Preclinical research
Microglia-neuron crosstalk via Hex-GM2-MGL2 maintains brain homeostasis
Original Paper | Diseases of the nervous system | 2025-08-05 20:00 EDT
Maximilian Frosch, Takashi Shimizu, Emile Wogram, Lukas Amann, Lars Gruber, Ayelén I. Groisman, Maximilian Fliegauf, Marius Schwabenland, Chintan Chhatbar, Sabrina Zechel, Hendrik Rosewich, Jutta Gärtner, Francisco J. Quintana, Joerg M. Buescher, Thomas Blank, Harald Binder, Christine Stadelmann, Johannes J. Letzkus, Carsten Hopf, Takahiro Masuda, Klaus-Peter Knobeloch, Marco Prinz
As tissue resident macrophages of the central nervous system (CNS) parenchyma, microglia perform diverse essential functions during homeostasis and perturbations1. They primarily interact with neurons via synaptic engulfment and through the rapid elimination of apoptotic cells and nonfunctional synapses2. Here, by combining unbiased lipidomics and high resolution spatial lipid imaging, deep single-cell transcriptome analysis and novel cell type-specific mutants, we identified a previously unknown mode of microglial interaction with neurons. During homeostasis, microglia deliver the lysosomal enzyme β-hexosaminidase (Hex) to neurons for the degradation of the ganglioside GM2 that is integral to maintaining cell membrane organization and function. Absence of Hexb, encoding the β subunit of Hex, in both mice and patients suffering from neurodegenerative Sandhoff disease leads to a massive accumulation of GM2 derivatives in a characteristic spatiotemporal manner3. In mice, neuronal GM2 gangliosides subsequently engage the macrophage galactose-type lectin (MGL)2 receptor on microglia via N-acetylgalactosamine (GalNAc) residues, leading to lethal neurodegeneration. Notably, replacement of microglia with peripherally derived microglia-like cells (MLCs) is able to break this degenerative cycle and fully restore CNS homeostasis. Our results reveal a novel mode of bidirectional microglia-neuron communication centred around GM2 ganglioside turnover, identify a novel microgliopathy and offer novel therapeutic avenues for these maladies.
Diseases of the nervous system, Gliogenesis
Whole-genome sequencing of 490,640 UK Biobank participants
Original Paper | Genetics research | 2025-08-05 20:00 EDT
Keren Carss, Bjarni V. Halldorsson, Liping Hou, Jimmy Liu, Eleanor Wheeler, Yancy Lo, Kousik Kundu, Zhuoyi Huang, Ben Lacey, Ryan S. Dhindsa, Diana Rajan, Jelena Randjelovic, Neil Marriott, Carol E. Scott, Ahmet Sinan Yavuz, Ian Johnston, Trevor Howe, Mary Helen Black, Kari Stefansson, Robert Scott, Slavé Petrovski, Shuwei Li, Adrian Cortes, Fengyuan Hu, Quanli Wang, Oliver S. Burren, Sri V. V. Deevi, Carolina Haefliger, Kieren Lythgow, Peter H. Maccallum, Karyn Mégy, Jonathan Mitchell, Sean O’Dell, Amanda O’Neill, Katherine R. Smith, Haeyam Taiy, Menelas Pangalos, Ruth March, Sebastian Wasilewski, Hannes P. Eggertsson, Kristjan H. S. Moore, Hannes Hauswedell, Ogmundur Eiriksson, Aron Skaftason, Nokkvi Gislason, Svanhvit Sigurjonsdottir, Magnus O. Ulfarsson, Gunnar Palsson, Marteinn T. Hardarson, Asmundur Oddsson, Brynjar O. Jensson, Snaedis Kristmundsdottir, Brynja D. Sigurpalsdottir, Olafur A. Stefansson, Doruk Beyter, Guillaume Holley, Vinicius Tragante, Arnaldur Gylfason, Pall I. Olason, Florian Zink, Margret Asgeirsdottir, Sverrir T. Sverrisson, Brynjar Sigurdsson, Sigurjon A. Gudjonsson, Gunnar T. Sigurdsson, Gisli H. Halldorsson, Gardar Sveinbjornsson, Unnur Styrkarsdottir, Droplaug N. Magnusdottir, Steinunn Snorradottir, Kari Kristinsson, Emilia Sobech, Gudmar Thorleifsson, Frosti Jonsson, Pall Melsted, Ingileif Jonsdottir, Thorunn Rafnar, Hilma Holm, Hreinn Stefansson, Jona Saemundsdottir, Daniel F. Gudbjartsson, Olafur T. Magnusson, Gisli Masson, Unnur Thorsteinsdottir, Agnar Helgason, Hakon Jonsson, Patrick Sulem, Jatin Sandhuria, Tom G. Richardson, Laurence Howe, Chloe Robins, Dongjing Liu, Patrick Albers, Mariana Pereira, Daniel Seaton, Yury Aulchenko, John Whittaker, Manolis Dermitzakis, Toby Johnson, Jonathan Davitte, Erik Ingelsson, Julio Molineros, Yanfei Zhang, Alexander H. Li, Evan H. Baugh, Elisabeth Mlynarski, Abolfazl Doostparast Torshizi, Gamal Abdel-Azim, Brian Mautz, Karen Y. He, Jingyue Xi, Shirley Nieves-Rodriguez, Asif Khan, Songjun Xu, Xingjun Liu, Brice Sarver, Dongnhu Truong, Mohamed-Ramzi Temanni, Christopher D. Whelan, Letizia Goretti, Najat Khan, Belen Fraile, Tommaso Mansi, Guna Rajagopal, Shaheen Akhtar, Siobhan Austin-Guest, Robert Barber, Daniel Barrett, Tristram Bellerby, Adrian Clarke, Richard Clark, Maria Coppola, Linda Cornwell, Abby Crackett, Joseph Dawson, Callum Day, Alexander Dove, Jillian Durham, Robert Fairweather, Marcella Ferrero, Michael Fenton, Howerd Fordham, Audrey Fraser, Paul Heath, Emily Heron, Gary Hornett, Lena Hughes-Hallett, David K. Jackson, Alexander Jakubowski Smith, Adam Laverack, Katharine Law, Steven R. Leonard, Kevin Lewis, Jennifer Liddle, Alice Lindsell, Sally Linsdell, Jamie Lovell, James Mack, Henry Mallalieu, Irfaan Mamun, Ana Monteiro, Leanne Morrow, Barbora Pardubska, Alexandru Popov, Lisa Sloper, Jan Squares, Ian Still, Oprah Taylor, Sam Taylor, Jaime M. Tovar Corona, Elliott Trigg, Valerie Vancollie, Paul Voak, Danni Weldon, Alan Wells, Eloise Wells, Mia Williams, Sean Wright, Nevena Miletic, Lea Lenhardt Ackovic, Marijeta Slavkovic-Ilic, Mladen Lazarevic, Louise Aigrain, Nicholas Redshaw, Michael Quail, Lesley Shirley, Scott Thurston, Peter Ellis, Laura Grout, Natalie Smerdon, Emma Gray, Richard Rance, Cordelia Langford, Rory Collins, Mark Effingham, Naomi Allen, Jonathan Sellors, Simon Sheard, Mahesh Pancholi, Caroline Clark, Lucy Burkitt-Gray, Samantha Welsh, Daniel Fry, Rachel Watson, Lauren Carson, Alan Young, Rami Mehio, Ole Schulz-Trieglaff
Whole-genome sequencing provides an unbiased and complete view of the human genome and enables the discovery of genetic variation without the technical limitations of other genotyping technologies. Here we report on whole-genome sequencing of 490,640 UK Biobank participants, building on previous genotyping effort1. This advance deepens our understanding of how genetics associates with disease biology and further enhances the value of this open resource for the study of human biology and health. Coupling this dataset with rich phenotypic data, we surveyed within- and cross-ancestry genomic associations and identified novel genetic and clinical insights. Although most associations with disease traits were primarily observed in individuals of European ancestries, strong or novel signals were also identified in individuals of African and Asian ancestries. With the improved ability to accurately genotype structural variants and exonic variation in both coding and UTR sequences, we strengthened and revealed novel insights relative to whole-exome sequencing2,3 analyses. This dataset, representing a large collection of whole-genome sequencing data that is available to the UK Biobank research community, will enable advances of our understanding of the human genome, facilitate the discovery of diagnostics and therapeutics with higher efficacy and improved safety profile, and enable precision medicine strategies with the potential to improve global health.
Genetics research, Genome-wide association studies, Next-generation sequencing, Rare variants
Novel assembly of a head-trunk interface in the sister group of jawed vertebrates
Original Paper | Evolutionary developmental biology | 2025-08-05 20:00 EDT
Tetsuto Miyashita, Philippe Janvier, Kristen Tietjen, Felisa Berenguer, Sebastian Schöder, Federica Marone, Pierre Gueriau, Michael I. Coates
The standard scenario for the origin of jawed vertebrates depicts a transition from benthic grazers to nektonic predators1,2,3, facilitated by a suite of anatomical innovations, including elaborate sensory systems, a high-flow heart and the integration of jaw-opening muscles with the craniothoracic hinge4,5,6,7. However, the lamprey-like internal anatomy8,9,10,11,12,13 reconstructed for osteostracans, the sister group of jawed vertebrates, seem to lack these gnathostome traits, implying a morphological gap despite phylogenetic proximity. Here, using synchrotron-based X-ray microtomography on the model osteostracan Norselaspis glacialis, we reveal derived gnathostome traits straddling a uniquely ossified head-trunk interface in this jawless fish. The inner ear of Norselaspis shows sensory elaborations (enlarged pars inferior and sinus superior) acquired well before the origin of jaws. As in crown gnathostomes, paired venous drainage channels blood into a high-volume cardiac tract. We also confirm a feature not yet demonstrated in any other vertebrate, to our knowledge: the most anterior trunk nerve extends its single trunk to the pectoral fin. In this respect, our reconstruction challenges the hypotheses14,15,16 that the gnathostome shoulder evolved from the gill apparatus. Our observations highlight Norselaspis as a prelude to the intercalation of the muscular neck and throat that would power the early jaw apparatus. Therefore, the vertebrate jaw–often considered the functional driver for ‘gnathostome’ innovations1,2,3–evolved instead as a follower to the sensory enhancement, increased cardiac output and greater locomotory control now inferred in the jawless sister group.
Evolutionary developmental biology, Ichthyology, Palaeontology
Hominins on Sulawesi during the Early Pleistocene
Original Paper | Archaeology | 2025-08-05 20:00 EDT
Budianto Hakim, Unggul Prasetyo Wibowo, Gerrit D. van den Bergh, Dida Yurnaldi, Renaud Joannes-Boyau, Akin Duli, Suryatman, Ratno Sardi, Indah Asikin Nurani, Mika Rizki Puspaningrum, Irfan Mahmud, Afdalah Haris, Khairun Al Anshari, Andi Muhammad Saiful, P. Arman Bungaran, Shinatria Adhityatama, Putra Hudlinas Muhammad, Anwar Akib, Nani Somba, Fakhri, Basran Burhan, Zubair Mas’ud, Mark W. Moore, Yinika L. Perston, Wenjing Yu, Maxime Aubert, Adam Brumm
The dispersal of archaic hominins beyond mainland Southeast Asia (Sunda)1 represents the earliest evidence for humans crossing ocean barriers to reach isolated landmasses2,3,4. Previously, the oldest indication of hominins in Wallacea, the oceanic island zone east of Sunda, comprised flaked stone artefacts deposited at least 1.02 ± 0.02 million years ago (Ma) at Wolo Sege on Flores5. Early hominins were also established on the oceanic island of Luzon (Philippines), as indicated by both stone artefacts and cut marks on faunal remains dating to between 777 and 631 thousand years ago (ka) at Kalinga6. Moreover, fossils of extinct, small-bodied hominins occur on Flores (Homo floresiensis)7,8,9,10,11,12 and Luzon (Homo luzonensis)13. On Sulawesi, the largest Wallacean island, previous excavations revealed stone artefacts with a minimum age of 194 ka at the open site of Talepu in the Walanae Depression14, long preceding the earliest known presence of modern humans (Homo sapiens) in the region (73-63 ka in Sunda)15. Here we show that stone artefacts also occur at the nearby site of Calio in fossiliferous layers dated to at least 1.04 Ma and possibly up to 1.48 Ma, using palaeomagnetic dating of sedimentary rocks and coupled Uranium-series (U-series) and electron-spin resonance (US-ESR) dating of fossil teeth. The discovery of Early Pleistocene artefacts at Calio suggests that Sulawesi was populated by hominins at around the same time as Flores, if not earlier.
Archaeology, Palaeoecology
RNA N-glycosylation enables immune evasion and homeostatic efferocytosis
Original Paper | Innate immunity | 2025-08-05 20:00 EDT
Vincent R. Graziano, Jennifer Porat, Marie Dominique Ah Kioon, Ivana Mejdrová, Alyssa J. Matz, Charlotta G. Lebedenko, Peiyuan Chai, John V. Pluvinage, Rafael Ricci-Azevedo, Andrew G. Harrison, Skylar S. Wright, Xinzheng Wang, Madison S. Strine, Penghua Wang, Michael R. Wilson, Sivapriya Kailasan Vanaja, Beiyan Zhou, Franck J. Barrat, Thomas Carell, Ryan A. Flynn, Vijay A. Rathinam
Glycosylation is central to the localization and function of biomolecules1. We recently discovered that small RNAs undergo N-glycosylation2 at the modified RNA base 3-(3-amino-3-carboxypropyl) uridine (acp3U)3. However, the functional significance of N-glycosylation of RNAs is unknown. Here we show that the N-glycans on glycoRNAs prevent innate immune sensing of endogenous small RNAs. We found that de-N-glycosylation of cell-culture-derived and circulating human and mouse glycoRNA elicited potent inflammatory responses including the production of type I interferons in a Toll-like receptor 3- and Toll-like receptor 7-dependent manner. Furthermore, we show that N-glycans on cell surface RNAs prevent apoptotic cells from triggering endosomal RNA sensors in efferocytes, thus facilitating the non-inflammatory clearance of dead cells. Mechanistically, N-glycans conceal the hypermodified uracil base acp3U, which we identified as immunostimulatory when exposed in RNA. Consistent with this, genetic deletion of an enzyme (DTWD2) that synthesizes acp3U abrogated innate immune activation by de-N-glycosylated small RNAs and apoptotic cells. Furthermore, synthetic acp3U-containing RNAs are sufficient to trigger innate immune responses. Thus, our study has uncovered a natural mechanism by which N-glycans block RNAs from inducing acp3U-dependent innate immune activation, demonstrating how glycoRNAs exist on the cell surface and in the endosomal network without inducing autoinflammatory responses.
Innate immunity, RNA
In situ light-field imaging of octopus locomotion reveals simplified control
Original Paper | Biomedical engineering | 2025-08-05 20:00 EDT
Kakani Katija, Christine L. Huffard, Paul L. D. Roberts, Joost Daniels, Jon Erickson, Denis Klimov, Henry A. Ruhl, Alana D. Sherman
Animals have developed many different solutions to survive, and these abilities are inspiring technological innovations in a wide range of fields including robotics1,2,3. However, biologically inspired robots, especially those mimicking octopus locomotion4,5, are based on limited in situ behavioural data owing to the complexity of collecting quantitative observations. Here we describe deployments of a remotely operated vehicle, equipped with a suite of imaging systems, to study the mechanics of locomotion in the octopus Muusoctopus robustus at the recently discovered 3,000-m deep Octopus Garden. Using a recently developed light-field imaging system called EyeRIS and an ultra-high-definition science camera, we were able to capture wide and zoomed-in views to characterize whole-animal gaits in a completely unconstrained environment across multiple individuals. Furthermore, the real-time volumetric data captured using EyeRIS yielded quantitative kinematics measurements of individual octopus arms during crawling, showing regions of high curvature and strain concentrated at distinct arm locations. Our results indicate that M. robustus crawling patterns showed several elements of simplified control, with implications for the design of future octopus-inspired robots. Further developments and deployments of technologies such as EyeRIS, coupled with capable robotic vehicles, will enable mining of the deep ocean for biological inspiration.
Biomedical engineering, Marine biology, Motility
Microglia regulate GABAergic neurogenesis in prenatal human brain through IGF1
Original Paper | Developmental neurogenesis | 2025-08-05 20:00 EDT
Diankun Yu, Samhita Jain, Andi Wangzhou, Beika Zhu, Wenyuan Shao, Elena J. Coley-O’Rourke, Stacy De Florencio, JaeYeon Kim, Jennifer Ja-Yoon Choi, Mercedes F. Paredes, Tomasz J. Nowakowski, Eric J. Huang, Xianhua Piao
GABAergic neurons are essential cellular components of neural circuits. Their abundance and diversity have increased significantly in the human brain, contributing to the expanded cognitive capacity of humans1. However, the developmental mechanism underlying the extended production of GABAergic neurons in the human brain remains elusive. Here we uncovered the microglial regulation of the sustained proliferation of GABAergic progenitors and neuroblasts in the human medial ganglionic eminence (hMGE). We showed that microglia are preferentially distributed in the proliferating zone and identified insulin-like growth factor 1 (IGF1) and its receptor IGR1R as the predicted top ligand-receptor pair underlying microglia-progenitor communication in the prenatal hMGE. Using our newly developed neuroimmune hMGE organoids, which mimic the hMGE cytoarchitecture and developmental trajectory, we demonstrated that microglia-derived IGF1 promotes progenitor proliferation and production of GABAergic neurons. Conversely, IGF1-neutralizing antibodies and IGF1 knockout human embryonic stem-cell-induced microglia abolish the induced microglia-mediated progenitor proliferation. Together, these findings revealed a previously unappreciated role of microglia-derived IGF1 in promoting the proliferation of neural progenitors and the development of GABAergic neurons in the human brain.
Developmental neurogenesis, Microglia, Neural progenitors, Neuroimmunology, Neuronal development
NSD2 inhibitors rewire chromatin to treat lung and pancreatic cancers
Original Paper | Drug development | 2025-08-05 20:00 EDT
Jinho Jeong, Simone Hausmann, Hanyang Dong, Kacper Szczepski, Natasha M. Flores, Andy Garcia Gonzalez, Liyang Shi, Xiaoyin Lu, Joanna Lempiäinen, Moritz Jakab, Liyong Zeng, Tourkian Chasan, Eric Bareke, Rui Dong, Emma Carlson, Reinnier Padilla, Dylan Husmann, Julia Thompson, Gerry A. Shipman, Emily Zahn, Courtney A. Barnes, Laiba F. Khan, Liz Marie Albertorio-Sáez, Eva Brill, Vishnu Udayakumar Sunita Kumary, Matthew R. Marunde, Danielle N. Maryanski, Cheryl C. Szany, Bryan J. Venters, Carolina Lin Windham, Michal Eligiusz Nowakowski, Iwona Czaban, Mariusz Jaremko, Michael-Christopher Keogh, Kang Le, Michael J. Soth, Benjamin A. Garcia, Łukasz Jaremko, Jacek Majewski, Pawel K. Mazur, Or Gozani
NSD2 catalyses the epigenetic modification H3K36me2 (refs. 1,2) and is a candidate convergent downstream effector of oncogenic signalling in diverse malignancies3,4,5. However, it remains unclear whether the enzymatic activity of NSD2 is therapeutically targetable. Here we characterize a series of clinical-grade small-molecule catalytic NSD2 inhibitors (NSD2i) and show that the pharmacological targeting of NSD2 constitutes an epigenetic dependency with broad therapeutic efficacy in KRAS-driven preclinical cancer models. NSD2i inhibits NSD2 with single-digit nanomolar half-maximal inhibitory concentration potency and high selectivity over related methyltransferases. Structural analyses reveal that the specificity of NSD2i for NSD2 is due to competitive binding with S-adenosylmethionine and catalytic disruption through a binary-channel obstruction mechanism. Proteo-epigenomic and single-cell strategies in pancreatic and lung cancer models support a mechanism in which sustained NSD2i exposure reverses pathological H3K36me2-driven chromatin plasticity, re-establishing silencing at H3K27me3-legacy loci to curtail oncogenic gene expression programs. Accordingly, NSD2i impairs the viability of pancreatic and lung cancer cells and the growth of patient-derived xenograft tumours. Furthermore, NSD2i, which is well-tolerated in vivo, prolongs survival in advanced-stage autochthonous KRASG12C-driven pancreatic and lung tumours in mouse models to a comparable level as KRAS inhibition with sotorasib6. In these models, treatment with both a NSD2 inhibitor and sotorasib synergize to confer sustained survival with extensive tumour regression and elimination. Together, our work uncovers targeting of the NSD2-H3K36me2 axis as an actionable vulnerability in difficult to treat cancers and provides support for the evaluation of NSD2 and KRAS inhibitor combination therapies in a clinical setting.
Drug development, Histone post-translational modifications
High-accuracy laser spectroscopy of ${ {\bf{H}}}_{ {\bf{2}}}^{ {\boldsymbol{+}}}$ and the proton-electron mass ratio
Original Paper | Atomic and molecular interactions with photons | 2025-08-05 20:00 EDT
S. Alighanbari, M. R. Schenkel, V. I. Korobov, S. Schiller
The molecular hydrogen ions (MHI) are three-body systems suitable for advancing our knowledge in several domains: fundamental constants, tests of quantum physics, search for new interparticle forces, tests of the weak equivalence principle1 and, once the anti-molecule $\overline{p},\overline{p},{e}^{+}$ becomes available, new tests of charge-parity-time-reversal invariance and local position invariance1,2,3. To achieve these goals, high-accuracy laser spectroscopy of several isotopologues, in particular ${ {\rm{H}}}{2}^{+}$, is required4. Here we present a Doppler-free laser spectroscopy of a ${ {\rm{H}}}{2}^{+}$ rovibrational transition, achieving line resolutions as large as 2.2 × 1013. We accurately determine the transition frequency with 8 × 10-12 fractional uncertainty. We also determine the spin-rotation coupling coefficient with 0.1 kHz uncertainty and its value is consistent with the state-of-the-art theory prediction5. The combination of our theoretical and experimental ${ {\rm{H}}}_{2}^{+}$ data allows us to deduce a new value for the proton-electron mass ratio mp/me. It is in agreement with the value obtained from mass spectrometry and has 2.3 times lower uncertainty. From combined MHI, H/D and muonic H/D data, we determine the baryon mass ratio md/mp with 1.1 × 10-10 absolute uncertainty. The value agrees with the directly measured mass ratio6. Finally, we present a match between a theoretical prediction and an experimental result, with a fractional uncertainty of 8.1 × 10-12. Both results indicate a notable confirmation of the predictive power of quantum theory and the absence of beyond-the-standard-model effects at these levels.
Atomic and molecular interactions with photons, Optical metrology, Quantum metrology
Structural basis of fast N-type inactivation in Kv channels
Original Paper | Cryoelectron microscopy | 2025-08-05 20:00 EDT
Xiao-Feng Tan, Ana I. Fernández-Mariño, Yan Li, Tsg-Hui Chang, Kenton J. Swartz
Action potentials are generated by opening of voltage-activated sodium (Nav) and potassium (Kv) channels1, which can rapidly inactivate to shape the nerve impulse and contribute to synaptic facilitation and short-term memory1,2,3,4. The mechanism of fast inactivation was proposed to involve an intracellular domain that blocks the internal pore in both Nav5,6 and Kv7,8,9 channels; however, recent studies in Nav10,11 and Kv12,13 channels support a mechanism in which the internal pore closes during inactivation. Here we investigate the mechanism of fast inactivation in the Shaker Kv channel using cryo-electron microscopy, mass spectrometry and electrophysiology. We resolved structures of a fully inactivated state in which the non-polar end of the N terminus plugs the internal pore in an extended conformation. The N-terminal methionine is deleted, leaving an alanine that is acetylated and interacts with a pore-lining isoleucine residue where RNA editing regulates fast inactivation14. Opening of the internal activation gate is required for fast inactivation because it enables the plug domain to block the pore and repositions gate residues to interact with and stabilize that domain. We also show that external K+ destabilizes the inactivated state by altering the conformation of the ion selectivity filter rather than by electrostatic repulsion. These findings establish the mechanism of fast inactivation in Kv channels, revealing how it is regulated by RNA editing and N-terminal acetylation, and providing a framework for understanding related mechanisms in other voltage-activated channels.
Cryoelectron microscopy, Neurophysiology
Excised DNA circles from V(D)J recombination promote relapsed leukaemia
Original Paper | Haematological cancer | 2025-08-05 20:00 EDT
Zeqian Gao, James N. F. Scott, Matthew P. Edwards, Dylan Casey, Xiaoling Wang, Andrew D. Gillen, Sarra Ryan, Lisa J. Russell, Anthony V. Moorman, Ruth de Tute, Catherine Cargo, Anthony M. Ford, David R. Westhead, Joan Boyes
Extrachromosomal DNA amplification is associated with poor cancer prognoses1. Large numbers of excised signal circles (ESCs) are produced as by-products of antigen receptor rearrangement during V(D)J recombination2,3. However, current dogma states that ESCs are progressively lost through cell division4. Here we show that ESCs replicate and persist through many cell generations and share many properties in common with circular extrachromosomal DNAs. Increased ESC copy numbers at diagnosis of B cell precursor acute lymphoblastic leukaemia were highly correlated with subsequent relapse. By taking advantage of the matching recombination footprint that is formed upon the generation of each ESC, we measured ESC persistence and replication and found increased ESC replication in patients who later relapsed. This increased replication is controlled by cell-intrinsic factors and corresponds to increased expression of DNA replication- and repair-associated genes. Consistent with high ESC levels having a role in disease progression, the number of mutations typical of those caused by the V(D)J recombinase-ESC complex was significantly increased at diagnosis in patients who later relapsed. The number of such mutations in genes associated with relapse increased between diagnosis and relapse, and corresponded to clonal expansion of cells with high ESC copy numbers. These data demonstrate that the by-product of V(D)J recombination, when increased in abundance, potently associates with the V(D)J recombinase to cause adverse disease outcomes.
Haematological cancer, Immunology, Molecular biology
A diverse and distinct microbiome inside living trees
Original Paper | Ecosystem ecology | 2025-08-05 20:00 EDT
Wyatt Arnold, Jonathan Gewirtzman, Peter A. Raymond, Marlyse C. Duguid, Craig R. Brodersen, Cade Brown, Naomi Norbraten, Qespi T’ika Vizcarra Wood, Mark A. Bradford, Jordan Peccia
Despite significant advances in microbiome research across various environments1, the microbiome of Earth’s largest biomass reservoir–the wood of living trees2–remains largely unexplored. Here, we illuminate the microbiome inhabiting and adapted to wood and further specialized to individual host tree species, revealing that wood is a harbour of biodiversity and potential key players in tree health and forest ecosystem functions. We demonstrate that a single tree hosts approximately one trillion bacteria in its woody tissues, with microbial communities distinctly partitioned between heartwood and sapwood, each maintaining unique microbiomes with minimal similarity to other plant tissues or ecosystem components. The heartwood microbiome emerges as a particularly unique ecological niche, distinguished by specialized archaea and anaerobic bacteria driving consequential biogeochemical processes. Our findings support the concept of plants as ‘holobionts’3,4–integrated ecological units of host and associated microorganisms–with implications for tree health, disease and functionality. By characterizing the composition, structure and functions of tree internal microbiomes, our work opens up pathways for understanding tree physiology and forest ecology and establishes a new frontier in environmental microbiology.
Ecosystem ecology, Forest ecology, Microbial ecology
Data-driven de novo design of super-adhesive hydrogels
Original Paper | Cheminformatics | 2025-08-05 20:00 EDT
Hongguang Liao, Sheng Hu, Hu Yang, Lei Wang, Shinya Tanaka, Ichigaku Takigawa, Wei Li, Hailong Fan, Jian Ping Gong
Data-driven methodologies have transformed the discovery and prediction of hard materials with well-defined atomic structures by leveraging standardized datasets, enabling accurate property predictions and facilitating efficient exploration of design spaces1,2,3. However, their application to soft materials remains challenging because of complex, multiscale structure-property relationships4,5,6. Here we present a data-driven approach that integrates data mining, experimentation and machine learning to design high-performance adhesive hydrogels from scratch, tailored for demanding underwater environments. By leveraging protein databases, we developed a descriptor strategy to statistically replicate protein sequence patterns in polymer strands by ideal random copolymerization, enabling targeted hydrogel design and dataset construction. Using machine learning, we optimized hydrogel formulations from an initial dataset of 180 bioinspired hydrogels, achieving remarkable improvements in adhesive strength, with a maximum value exceeding 1 MPa. These super-adhesive hydrogels hold immense potential across diverse applications, from biomedical engineering to deep-sea exploration, marking a notable advancement in data-driven innovation for soft materials.
Cheminformatics, Gels and hydrogels
Stronger El Niños reduce tropical forest arthropod diversity and function
Original Paper | Biodiversity | 2025-08-05 20:00 EDT
Adam C. Sharp, Michael J. W. Boyle, Timothy C. Bonebrake, Yirong Guo, Roger L. Kitching, Nigel E. Stork, Xiaoyi Zeng, Louise A. Ashton
There is ongoing debate about the vulnerability of arthropods to climate change1,2. Long-term impacts of climate change on arthropod communities could manifest through short-term weather patterns3. Arthropods in the tropics are hyper-diverse4,5 and contribute many crucial ecosystem functions6,7, but are comparatively less studied than in temperate regions1,8,9. Tropical forest arthropods and the functions that they provide may be vulnerable to intensified El Niño events under climate change10,11,12. Here we perform time-series analysis of data from primary tropical forests, which reveal long-term declines in arthropod diversity and function that were linked to El Niño occurrence. In the Americas, species losses correlated with El Niño sensitivity, and abundant species fluctuated according to feeding traits and level of ecological specialization. Parallel declines in butterflies in Southeast Asia suggested that impacts spanned continents. Predicted arthropod diversity changes correlated with observed rates of invertebrate-mediated decomposition and leaf herbivory, which were oscillating and crashing, respectively, across the tropics. Our analyses suggest that an intensified El Niño immediately threatens tropical forest arthropods and the ecosystem functions that they provide. The broader consequences remain unknown, but such widespread changes could fundamentally alter tropical forest ecosystems13. Long-term monitoring of arthropod diversity and forest functioning across the tropics is paramount, as is researching the potential mechanisms that underly this novel threat.
Biodiversity, Climate-change ecology, Tropical ecology
Optical control of resonances in temporally symmetry-broken metasurfaces
Original Paper | Metamaterials | 2025-08-05 20:00 EDT
Andreas Aigner, Thomas Possmayer, Thomas Weber, Alexander A. Antonov, Leonardo de S. Menezes, Stefan A. Maier, Andreas Tittl
Tunability in active metasurfaces has mainly relied on shifting the resonance wavelength1,2 or increasing material losses3,4 to spectrally detune or quench resonant modes, respectively. However, both methods face fundamental limitations, such as a limited Q factor and near-field enhancement control and the inability to achieve resonance on-off switching by completely coupling and decoupling the mode from the far field. Here we demonstrate temporal symmetry breaking in metasurfaces through ultrafast optical pumping, providing an experimental realization of radiative-loss-driven resonance tuning, allowing resonance creation, annihilation, broadening and sharpening. To enable this temporal control, we introduce restored symmetry-protected bound states in the continuum. Even though their unit cells are geometrically asymmetric, coupling to the radiation continuum remains fully suppressed, which, in this work, is achieved by two equally strong antisymmetric dipoles. By using selective Mie-resonant pumping in parts of these unit cells, we can modify their dipole balance to create or annihilate resonances as well as tune the linewidth, amplitude and near-field enhancement, leading to potential applications in optical and quantum communications, time crystals and photonic circuits.
Metamaterials, Nanophotonics and plasmonics, Ultrafast photonics
Lithium deficiency and the onset of Alzheimer’s disease
Original Paper | Alzheimer’s disease | 2025-08-05 20:00 EDT
Liviu Aron, Zhen Kai Ngian, Chenxi Qiu, Jaejoon Choi, Marianna Liang, Derek M. Drake, Sara E. Hamplova, Ella K. Lacey, Perle Roche, Monlan Yuan, Saba S. Hazaveh, Eunjung A. Lee, David A. Bennett, Bruce A. Yankner
The earliest molecular changes in Alzheimer’s disease (AD) are poorly understood1,2,3,4,5. Here we show that endogenous lithium (Li) is dynamically regulated in the brain and contributes to cognitive preservation during ageing. Of the metals we analysed, Li was the only one that was significantly reduced in the brain in individuals with mild cognitive impairment (MCI), a precursor to AD. Li bioavailability was further reduced in AD by amyloid sequestration. We explored the role of endogenous Li in the brain by depleting it from the diet of wild-type and AD mouse models. Reducing endogenous cortical Li by approximately 50% markedly increased the deposition of amyloid-β and the accumulation of phospho-tau, and led to pro-inflammatory microglial activation, the loss of synapses, axons and myelin, and accelerated cognitive decline. These effects were mediated, at least in part, through activation of the kinase GSK3β. Single-nucleus RNA-seq showed that Li deficiency gives rise to transcriptome changes in multiple brain cell types that overlap with transcriptome changes in AD. Replacement therapy with lithium orotate, which is a Li salt with reduced amyloid binding, prevents pathological changes and memory loss in AD mouse models and ageing wild-type mice. These findings reveal physiological effects of endogenous Li in the brain and indicate that disruption of Li homeostasis may be an early event in the pathogenesis of AD. Li replacement with amyloid-evading salts is a potential approach to the prevention and treatment of AD.
Alzheimer’s disease, Molecular neuroscience
A global humidity index with lateral hydrologic flows
Original Paper | Ecosystem ecology | 2025-08-05 20:00 EDT
Gonzalo Miguez-Macho, Ying Fan
The aridity index is widely used to indicate water availability on land. Balancing climatic water supply (precipitation, P) against demand (potential evapotranspiration, PET), it is often expressed as the P/PET ratio1 or humidity index. Water also flows laterally by rivers and groundwater, from hills to valleys and from mountains to plains, subsidizing the receiving lowlands2. Here, we show that this lateral subsidy reduces aridity in the receiving lowlands. We first estimate monthly subsidies (Qlat) by surface and groundwater at 30″ global grids with a global hydrology model. We then calculate the conventional global humidity index (GHI) as P/PET and a new GHI including Qlat as (P + Qlat)/PET. Termed GHI_topo, the latter reflects land topography, higher in hydrologically convergent lowlands. It also exhibits a delayed and dampened seasonality (relative to P) owing to delayed and diffused Qlat arrival at the receiving lowlands. Such spatiotemporal features of Qlat, arising from both the climate and the terrain, make GHI_topo a more realistic indicator of local water availability in downgradient societies and ecosystems, enabling life in arid locations and times. Global land area with GHI_topo ≥ 1 (supply meets or exceeds demand) is 33% greater than GHI ≥ 1 and far higher in arid and season-arid climates.
Ecosystem ecology, Hydrology
EBV induces CNS homing of B cells attracting inflammatory T cells
Original Paper | Autoimmunity | 2025-08-05 20:00 EDT
Fabienne Läderach, Ioannis Piteros, Éanna Fennell, Elena Bremer, Mette Last, Sandra Schmid, Lisa Rieble, Caroline Campbell, Isis Ludwig-Portugall, Lea Bornemann, Alexander Gruhl, Klaus Eulitz, Paul Gueguen, Juliane Mietz, Anne Müller, Gaetana Pezzino, Jürgen Schmitz, Guido Ferlazzo, Josef Mautner, Christian Münz
Epidemiological data have identified Epstein-Barr virus (EBV) infection as the main environmental risk factor for multiple sclerosis, the predominant autoimmune disease of the central nervous system (CNS)1. However, how EBV infection initiates multiple sclerosis pathogenesis remains unclear. Here we demonstrate that EBV expands oligoclonal T-bet+CXCR3+ B cells that home to the CNS in humanized mice. Effector memory CD8+ T cells and CD4+ TH1 cells as well as CD4+ TH17 cells co-migrate to the brain of EBV-infected humanized mice. T-bet+CXCR3+ B cells can colonize submeningeal brain regions in the absence of other lymphocytes and attract T cells. Depletion of B cells with rituximab or blocking of CXCR3 significantly decreases lymphocyte infiltration into the CNS. Thus, we suggest that symptomatic primary EBV infection generates B cell subsets that gain access to the CNS, attract T cells and thereby initiate multiple sclerosis.
Autoimmunity, Herpes virus, Multiple sclerosis
The science fiction science method
Review Paper | Human behaviour | 2025-08-05 20:00 EDT
Iyad Rahwan, Azim Shariff, Jean-François Bonnefon
Predicting the social and behavioural impact of future technologies before they are achieved would enable us to guide their development and regulation before these impacts get entrenched. Traditionally, this prediction has relied on qualitative, narrative methods. Here we describe a method that uses experimental methods to simulate future technologies and collect quantitative measures of the attitudes and behaviours of participants assigned to controlled variations of the future. We call this method ‘science fiction science’. We suggest that the reason that this method has not been fully embraced yet, despite its potential benefits, is that experimental scientists may be reluctant to engage in work that faces such serious validity threats. To address these threats, we consider possible constraints on the types of technology that science fiction science may study, as well as the unconventional, immersive methods that it may require. We seek to provide perspective on the reasons why this method has been marginalized for so long, the benefits it would bring if it could be built on strong yet unusual methods, and how we can normalize these methods to help the diverse community of science fiction scientists to engage in a virtuous cycle of validity improvement.
Human behaviour, Interdisciplinary studies, Society
One-third of Sun-like stars are born with misaligned planet-forming disks
Original Paper | Early solar system | 2025-08-05 20:00 EDT
Lauren I. Biddle, Brendan P. Bowler, Marvin Morgan, Quang H. Tran, Ya-Lin Wu
Exoplanets are organized in a broad array of orbital configurations1,2 that reflect their formation along with billions of years of dynamical processing through gravitational interactions3. This history is encoded in the angular momentum architecture of planetary systems–the relation between the rotational properties of the central star and the orbital geometry of planets. A primary observable is the alignment (or misalignment) between the rotational axis of the star and the orbital plane of its planets, known as stellar obliquity. Hundreds of spin-orbit constraints have been measured for giant planets close to their host stars4, many of which have revealed planets on misaligned orbits. A leading question that has emerged is whether stellar obliquity originates primarily from gravitational interactions with other planets or distant stars in the same system, or if it is ‘primordial’–imprinted during the star-formation process. Here we present a comprehensive assessment of primordial obliquities between the spin axes of young, isolated Sun-like stars and the orientation of the outer regions of their protoplanetary disks. Most systems are consistent with angular momentum alignment but about one-third of isolated young systems exhibit primordial misalignment. This suggests that some obliquities identified in planetary systems at older ages–including the Sun’s modest misalignment with planets in the Solar System–could originate from initial conditions of their formation.
Early solar system, Exoplanets, Stars, Stellar evolution
Parent-of-origin effects on complex traits in up to 236,781 individuals
Original Paper | Genome-wide association studies | 2025-08-05 20:00 EDT
Robin J. Hofmeister, Théo Cavinato, Roya Karimi, Adriaan van der Graaf, Fanny-Dhelia Pajuste, Jaanika Kronberg, Nele Taba, Andres Metspalu, Tõnu Esko, Mari Nelis, Georgi Hudjashov, Reedik Mägi, Marc Vaudel, Simone Rubinacci, Stefan Johansson, Lili Milani, Olivier Delaneau, Zoltán Kutalik
Parent-of-origin effects (POEs) occur when the effect of a genetic variant depends on its parental origin1. Traditionally linked to genomic imprinting, POEs are believed to occur due to parental conflict over resource allocation to offspring, resulting in opposing parental influences2. Despite their importance, POEs remain underexplored in complex traits, owing to the lack of parental genomes. Here we present an approach to infer the parent of origin of alleles without parental genomes, leveraging interchromosomal phasing, mitochondrial and X chromosome data, and sex-specific crossover in siblings. Applied to the UK Biobank, this enabled parent-of-origin inference for up to 109,385 individuals. Genome-wide association study scans for 59 complex traits and over 14,000 protein quantitative trait loci contrasting maternal and paternal effects identified over 30 POEs and confirmed more than 50% of known associations. More than one third of these showed opposite parental influences, especially for traits related to growth (for example, IGF1 and height) and metabolism (for example, type 2 diabetes and triglyceride levels). Replication in up to 85,050 individuals from the Estonian Biobank and 42,346 offspring from the Norwegian Mother, Father and Child Cohort Study (MoBa) validated 87% of testable associations. Overall, our findings highlight the contribution of POEs to complex traits and support the parental conflict hypothesis, providing compelling evidence for this understudied evolutionary phenomenon.
Genome-wide association studies, Haplotypes, Imprinting, Statistical methods
Kinetic turbulence drives MHD equilibrium change via 3D reconnection
Original Paper | Astrophysical plasmas | 2025-08-05 20:00 EDT
Jong Yoon Park, Young Dae Yoon, Yong-Seok Hwang
Cross-scale coupling from magnetohydrodynamics (MHD) to non-MHD scales is important in interpreting observations of explosive events in nature, such as solar flares and geomagnetic storms1,2. Experiments and observations also link it to the emergence of energetic particles and X-rays3. However, how this multi-scale physics affects the abrupt onset of reconnection remains unknown. Here we report observations from laboratory experiments involving two flux ropes with electron beams that induce magnetic turbulence and then abruptly merge into a single structure, altering the magnetic topology in the MHD regime. Two separate electron beams are launched along magnetic field lines and form individual flux ropes with a drift velocity higher than the ambient Alfvén velocity, effectively driving magnetic turbulence through beam-driven instabilities, as inferred from the increased level of the turbulent power spectrum. Experimental observations, including the appearance of energetic particles, increased ion temperature and changes in the characteristics of the flux ropes, suggest that beam-driven turbulence drives three-dimensional (3D) reconnection. 3D particle-in-cell simulations are performed, which successfully reproduce the key aspects of the experiment. These results directly explain how non-MHD kinetic processes progress through multiple scales to induce global MHD changes.
Astrophysical plasmas, Fluid dynamics, Magnetically confined plasmas
Nature Physics
High-purity quantum optomechanics at room temperature
Original Paper | Nanosensors | 2025-08-05 20:00 EDT
Lorenzo Dania, Oscar Schmitt Kremer, Johannes Piotrowski, Davide Candoli, Jayadev Vijayan, Oriol Romero-Isart, Carlos Gonzalez-Ballestero, Lukas Novotny, Martin Frimmer
Exploiting quantum effects in a mechanical oscillator, such as back-action-evading measurements or squeezing of the mechanical degrees of freedom, requires the oscillator to be prepared in a high-purity quantum state. The largest state purities in optomechanics to date have been achieved with costly cryogenic cooling combined with coupling to electromagnetic resonators driven with a coherent radiation field. Here we use coherent scattering into a Fabry-Pérot cavity to cool the megahertz-frequency librational mode of an optically levitated silica nanoparticle from room temperature to its quantum ground state. We use sideband thermometry to infer a phonon population of 0.04 quanta under optimal conditions, corresponding to a state purity of 92%. The purity reached by our room-temperature experiment exceeds the performance offered by mechanically clamped oscillators in a cryogenic environment, establishing a platform for high-purity quantum optomechanics at room temperature.
Nanosensors, Optical manipulation and tweezers, Quantum mechanics, Quantum metrology
Physical Review Letters
Critical Dynamics in Short-Range Quadratic Hamiltonians
Research article | Anomalous diffusion | 2025-08-05 06:00 EDT
Miroslav Hopjan and Lev Vidmar
We investigate critical transport and the dynamical exponent through the spreading of an initially localized particle in quadratic Hamiltonians with short-range hopping in lattice dimension ${d}{l}$. We consider critical dynamics that emerges when the Thouless time, i.e., the saturation time of the mean-squared displacement, approaches the typical Heisenberg time. We establish a relation, $z={d}{l}/{d}{s}$, linking the critical dynamical exponent $z$ to ${d}{l}$ and to the spectral fractal dimension ${d}{s}$. This result has notable implications: it says that superdiffusive transport in ${d}{l}\ge 2$ and diffusive transport in ${d}{l}\ge 3$ cannot be critical in the sense defined above. Our findings clarify previous results on disordered and quasiperiodic models and, through Fibonacci potential models in two and three dimensions, provide nontrivial examples of critical dynamics in systems with ${d}{l}\ne 1$ and ${d}_{s}\ne 1$.
Phys. Rev. Lett. 135, 060401 (2025)
Anomalous diffusion, Cold gases in optical lattices, Dynamic critical phenomena, Excited-state quantum phase transitions, Fractal analysis, Quantum transport, Disordered systems, Nonequilibrium lattice models, Exact diagonalization, Fractal dimension characterization
Scalable Improvement of the Generalized Toffoli Gate Realization Using Trapped-Ion-Based Qutrits
Research article | Quantum algorithms & computation | 2025-08-05 06:00 EDT
Anastasiia S. Nikolaeva, Ilia V. Zalivako, Alexander S. Borisenko, Nikita V. Semenin, Kristina P. Galstyan, Andrey E. Korolkov, Evgeniy O. Kiktenko, Ksenia Yu. Khabarova, Ilya A. Semerikov, Aleksey K. Fedorov, and Nikolay N. Kolachevsky
An efficient implementation of the Toffoli gate is of conceptual importance for running various quantum algorithms, including Grover’s search and Shor’s integer factorization. However, direct implementation of the Toffoli gate either entails a prohibitive increase in the number of two-qubit gates or requires ancilla qubits, whereas both of these resources are limited in the current generation of noisy intermediate-scale quantum devices. Here, we experimentally demonstrate a scalable $N$-qubit Toffoli gate improvement using $^{171}{\mathrm{Yb}}^{+}$ trapped-ion-based optical-metastable-ground encoded qutrits for the cases of up to $N=10$. With the use of the M\o{}lmer-S\o{}rensen gate as a basic entangling operation, we compare the standard qubit decomposition with the qutrit approach, where upper levels are used as ancillae. The presented decomposition requires only global control of the ancilla levels, which simplifies experimental implementation of the proposed approach. Using the example of a three-qubit Grover’s search, we also demonstrate an increase in the algorithm’s accuracy by monitoring the leakage from the qubit subspace during a qutrit-based Toffoli gate implementation.
Phys. Rev. Lett. 135, 060601 (2025)
Quantum algorithms & computation, Quantum circuits, Quantum gates, Quantum information with trapped ions, Qudits, Ions
Continuous-Variable Designs and Design-Based Shadow Tomography from Random Lattices
Research article | Quantum error correction | 2025-08-05 06:00 EDT
Jonathan Conrad, Joseph T. Iosue, Ansgar G. Burchards, and Victor V. Albert
We investigate state designs for continuous-variable quantum systems using the aid of latticelike quantum states. These are code states of Gottesman-Kitaev-Preskill (GKP) codes. We show that the set of all GKP states forms a rigged continuous-variable state 2-design for an $n$-mode system. We use these lattice state designs to construct a continuous variable shadow tomography protocol, derive sample complexity bounds for both global and local GKP shadows under reasonable physical assumptions, and provide the physical gadgets needed to implement this protocol.
Phys. Rev. Lett. 135, 060802 (2025)
Quantum error correction, Quantum information processing, Quantum information theory, Quantum measurements, Quantum metrology
Nature of Phase Transitions and Metastability in Scalar-Tensor Theories
Research article | Alternative gravity theories | 2025-08-05 06:00 EDT
K𝚤vanç İ. Ünlütürk, Semih Tuna, Oğuzhan K. Yamak, and Fethi M. Ramazanoğlu
Compact stars above a critical stellar mass develop large scalar fields in some scalar-tensor theories. This scenario called spontaneous scalarization has been an intense topic of study since it passes weak-field gravity tests naturally while providing clear observables in the strong-field regime. The underlying mechanism for the onset of scalarization is often depicted as a second-order phase transition. Here, we show that a first-order phase transition is in fact the most common mechanism. This means metastability and transitions between locally stable compact object configurations are much more likely than previously believed, opening vast new avenues for observational prospects.
Phys. Rev. Lett. 135, 061401 (2025)
Alternative gravity theories, Phase transitions, Neutron stars & pulsars
Universality of R'enyi Entropy in Conformal Field Theory
Research article | Conformal field theory | 2025-08-05 06:00 EDT
Yuya Kusuki, Hirosi Ooguri, and Sridip Pal
A calculation using thermal effective theory proves new universal behaviors of Rényi entropy for conformal field theories in arbitrary dimensions.
Phys. Rev. Lett. 135, 061603 (2025)
Conformal field theory, Effective field theory, Entanglement in field theory, Higher-dimensional field theories, Symmetries
Time-Dependent Density Functional Theory Description of $^{238}\mathrm{U}(\mathrm{n},\mathrm{f})$, $^{240,242}\mathrm{Pu}(\mathrm{n},\mathrm{f})$, and $^{237}\mathrm{Np}(\mathrm{n},\mathrm{f})$ Reactions
Research article | Fission | 2025-08-05 06:00 EDT
Aurel Bulgac, Ibrahim Abdurrahman, Matthew Kafker, and Ionel Stetcu
In nuclei with an odd nucleon number the nonvanishing spin number density is the source of a pseudomagnetic field, which favors the splitting of the nucleon Cooper pairs. Such a pseudomagnetic field is generated always in the dynamics of any nucleus, but its effects on Cooper pairs are significantly enhanced in the dynamic evolution of nuclei with an odd number of nucleons. We present for the first time a microscopic study of the induced fission of the odd neutron compound nuclei $^{239}\mathrm{U}$, $^{241,243}\mathrm{Pu}$, and the odd proton, odd neutron compound nucleus $^{238}\mathrm{Np}$, performed within the time-dependent density functional theory extended to superfluid fermion systems, without any simplifying assumptions, with controlled numerical approximations, and for a very large number of initial conditions. Because of the presence of the unpaired odd nucleon(s), the time-reversal symmetry of the fission compound nucleus is spontaneously broken, an aspect routinely neglected in the most advanced microscopic approaches of the past. The emerging fission fragment properties are quite similar to the properties of fission fragments of neighboring even-even nuclei. The time from saddle-to-scission is often significantly longer in odd-odd or odd-mass nuclei than for even-even nuclei, since systems with unpaired nucleons are easier to excite and the potential energy surfaces of these nuclei have more structure, often resembling a very complicated obstacle course, rather than a more direct evolution of the nuclear shape from the top of the outer fission barrier to the scission configuration. The Pauli blocking approximation, often invoked in the literature, expected to inhibit the fission of nuclei with unpaired nucleons, is surprisingly strongly violated during the fission dynamics.
Phys. Rev. Lett. 135, 062501 (2025)
Fission, Nuclear density functional theory
Cryogenic Optical Lattice Clock with $1.7\times{}{10}^{- 20}$ Blackbody Radiation Stark Uncertainty
Research article | Atomic, optical & lattice clocks | 2025-08-05 06:00 EDT
Youssef S. Hassan, Kyle Beloy, Jacob L. Siegel, Takumi Kobayashi, Eric Swiler, Tanner Grogan, Roger C. Brown, Tristan Rojo, Tobias Bothwell, Benjamin D. Hunt, Adam Halaoui, and Andrew D. Ludlow
A new experimental design eliminates the top source of clock uncertainty.
Phys. Rev. Lett. 135, 063402 (2025)
Atomic, optical & lattice clocks, Cryogenics & vacuum technology, Metrology, Stark effect, Trapped atoms, Optical lattices & traps
Electrically Induced Bulk and Edge Excitations in the Fractional Quantum Hall Regime
Research article | Edge states | 2025-08-05 06:00 EDT
Quentin France, Yunhyeon Jeong, Akinori Kamiyama, Takaaki Mano, Ken-ichi Sasaki, Masahiro Hotta, and Go Yusa
We apply a voltage pulse to electrically excite the incompressible region of a two-dimensional electron liquid in the $\nu =2/3$ fractional quantum Hall state and investigate the collective excitations in both the bulk and edge via photoluminescence spectral energy shifts. Introducing an offset in the voltage pulse significantly enhances the excitation signal. Real-space and time-resolved measurements reveal the dynamics of the bulk excitations, with an estimated group velocity of approximately $3\times{}{10}^{4}\text{ }\text{ }\mathrm{m}/\mathrm{s}$. These bulk excitations align well with the magnetoplasmon model. Because bulk and edge magnetoplasmons are composed of two polarization degrees of freedom of the gauge field, our results highlight a connection that could serve as a resource for their entanglement—similar to the polarization of a photon—and offer a novel approach to exploring solid-state analogs of quantum gravity.
Phys. Rev. Lett. 135, 066203 (2025)
Edge states, Fractional quantum Hall effect, Surface plasmons, Topological materials, Gravitons, Conformal symmetry, Spectroscopy, Time-resolved photoluminescence
Dynamically Induced Multiferroic Polarization
Research article | Optical phonons | 2025-08-05 06:00 EDT
Carolina Paiva, Michael Fechner, and Dominik M. Juraschek
We describe a mechanism by which both a ferroelectric polarization and a magnetization can be created in nonpolar, nonmagnetic materials. Using a combination of phenomenological modeling and first-principles calculations, we demonstrate that ferroelectric polarization, magnetization, or both simultaneously can be transiently induced by an ultrashort laser pulse upon linearly, circularly, or elliptically polarized excitation of phonon modes in $\gamma \text{- }{\text{LiBO}}_{2}$. The direction and magnitude of the multiferroic polarization can be controlled by the chirality of the laser pulse and the phonon modes, offering a pathway for controlling multiferroicity and magnetoelectricity on ultrafast timescales.
Phys. Rev. Lett. 135, 066702 (2025)
Optical phonons, Ultrafast magnetization dynamics, Ferroelectrics, Multiferroics, Density functional theory
Multistate Geometry of Shift Current and Polarization
Research article | Electric polarization | 2025-08-05 06:00 EDT
Alexander Avdoshkin, Johannes Mitscherling, and Joel E. Moore
The quantum metric and Berry curvature capture essential properties of nontrivial Bloch states and underpin many fascinating phenomena. However, it becomes increasingly evident that a more comprehensive understanding of quantum state geometry is necessary to explain properties involving Bloch states of multiple bands, such as optical transitions. To this end, we employ quantum state projectors to develop an explicitly gauge-invariant formalism and demonstrate its power with applications to nonlinear optics and the theory of electronic polarization. We provide a simple expression for the shift current that resolves its precise relation to the moments of electronic polarization, clarifies the treatment of band degeneracies, and reveals its decomposition into the sum of the skewness of the occupied states and intrinsically multistate geometry. The projector approach is applied to calculate nonlinear optical properties of transition metal dichalcogenides (TMDs) layers, using previously calculated minimal tight-binding models, and demonstrated analytically on a three-band generalization of the Rice-Mele chain to elucidate the different contributions. We close with comments on further applications of the projector operator approach to multistate geometry.
Phys. Rev. Lett. 135, 066901 (2025)
Electric polarization, Geometric & topological phases, Optical conductivity, Photovoltaic effect, Shift current, Topological materials, Insulators, Semimetals, Transition metal dichalcogenides, Lattice models in condensed matter, Tight-binding model
Mach Reflection and Expansion of Two-Dimensional Dispersive Shock Waves
Research article | Continuum mechanics | 2025-08-05 06:00 EDT
Gino Biondini, Alexander Bivolcic, and Mark A. Hoefer
The oblique collisions and dynamical interference patterns of two-dimensional dispersive shock waves are studied numerically and analytically via the temporal dynamics induced by wedge-shaped initial conditions for the Kadomtsev-Petviashvili II equation. Various asymptotic wave patterns are identified, classified, and characterized in terms of the incidence angle and the amplitude of the initial step, which can give rise to either subcritical or supercritical configurations, including the generalization to dispersive shock waves of the Mach reflection and expansion of viscous shocks and line solitons. An eightfold amplification of the amplitude of an obliquely incident flow upon a wall at the critical angle is demonstrated. Applications of the results include bore interactions in geophysical fluid dynamics.
Phys. Rev. Lett. 135, 067201 (2025)
Continuum mechanics, Nonlinear waves, Solitons
Real 2D Galvanostatic Model: Encoding Physicochemical Heterogeneity into a Full Battery
Research article | Batteries | 2025-08-05 06:00 EDT
Zhe-Tao Sun, Shiwei Chen, Teng Zhao, Yunlong Guo, Zhenli Xu, Shenggao Zhou, and Shou-Hang Bo
The propagation of physicochemical heterogeneity from particles to electrodes under galvanostatic cycling conditions largely determines battery performance but is often computationally unreachable. We formulate a Real 2D (R2D) full-battery model via an electrode-adaptive mathematical framework that addresses the electrochemically correlated nonlinear current-potential responses of the electrodes. This allows us to quantify the impact of multiphysics coupling on cycling performance in emerging solid-state batteries. R2D advances the modeling efficiency and can be generally applied to heterogeneous battery systems, providing a new pathway for accurate full battery simulations.
Phys. Rev. Lett. 135, 068001 (2025)
Batteries, Chemical kinetics, dynamics & catalysis, Complex systems, Electrochemistry, Lithium batteries, Solid-state batteries, Solid-state chemistry, Thermodynamics of computation
arXiv
Quantum Geometry of Altermagnetic Magnons Probed by Light
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-08-06 20:00 EDT
Rundong Yuan, Wojciech J. Jankowski, Ka Shen, Robert-Jan Slager
Magnons with momentum-dependent chirality are a key signature of altermagnets. We identify bicircular light as a smoking-gun optical probe for chiral altermagnetic magnons, selectively targeting their quantum geometry induced by an alteration of magnonic chirality. We show that in $ d$ -wave altermagnets, under a canting magnetic field, the altermagnetic magnons realize a nontrivial quantum geometry, resulting in an enhancement of the nonlinear second-order light-magnon interactions. We find that the scattering of bicircular pulses probes the present magnon quantum geometry, even if the magnonic topology is trivial. Hence, our findings establish bicircular Raman response as an optical effect of choice to identify altermagnetic magnons. As such, we propose a universal experimental protocol to distinguish altermagnets from antiferromagnets by detecting their magnon chirality patterns with light, independently of the underlying magnon topology.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci), Optics (physics.optics), Quantum Physics (quant-ph)
9+4 pages, 4+3 figures
Nonreciprocal Model B: The role of mobilities and nonreciprocal interfacial forces
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-08-06 20:00 EDT
Bibhut Sahoo, Rituparno Mandal, Peter Sollich
We study a non-reciprocal version of Model B, as the continuum theory for non-reciprocal particle mixtures. In contrast to non-reciprocal Cahn-Hilliard models, it is important in this context to consider the dependence of mobility coefficients on the local concentrations. We show that a homogeneous state that is linearly stable for one form of the mobility can be unstable for a different form of mobility, an effect that would be impossible in equilibrium and implies a crucial role for mobilities in non-reciprocal mixtures. For unstable homogeneous states we study the spinodal dynamics governing the onset of phase separation. We find, again in contrast to non-reciprocal Cahn-Hilliard models, that exceptional point transitions between static and oscillatory instabilities are generically avoided by first order transitions where the spinodal lengthscale changes discontinuously. At these transitions we find intricate spinodal dynamics with two competing lengthscales, one governing a static instability and the other an oscillatory instability, i.e. one that generates travelling waves. We demonstrate that, depending on interaction strengths, more complex transitions can occur in the spinodal dynamics, including coexistence of three lengthscales and first order transition lines, terminated by critical points, between distinct static instabilities. Finally, we explore the effects of additional non-reciprocity in the interfacial chemical potentials, which would generically be expected when obtaining Model B by coarse graining from a non-reciprocal particle model. We show that interfacial non-reciprocity can increase the region in the spinodal phase diagram where oscillatory instabilities occur, but only up to a certain boundary that we establish analytically and demonstrate numerically.
Soft Condensed Matter (cond-mat.soft), Statistical Mechanics (cond-mat.stat-mech), Pattern Formation and Solitons (nlin.PS)
11 pages, 7 figures
Signatures of quantum chaos and complexity in the Ising model on random graphs
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2025-08-06 20:00 EDT
We investigate signatures of quantum chaos and complexity in the quantum annealing Ising model on random Erdős-Rényi graphs. By tuning the connectivity of the graph, the dynamics can be driven from a localized phase through a chaotic regime to an integrable limit. While this dynamical transition reflects in the spectral characteristics, we pursue a broader suite of quantum chaos indicators,some of which can be measured on near-term quantum devices. We study deep thermalization of a quantum state ensemble obtained from a natural unraveling of the subsystem density matrix as an indicator of chaotic dynamics. This extends the analysis of quantum chaos to the ensemble of quantum states. Furthermore, we analyze the eigenstate and eigenvalue correlations through the partial spectral form factor of subsystems and observe distinct signatures of the onset of chaos and its system size dependence, providing experimentally measurable indicators of the localization-to-chaos transition. As a locality-independent probe, we show that the Krylov complexity of operators is also maximized in the chaotic regime, providing a link between graph topology and information scrambling. Finally, we investigate a quantum analogue of the Mpemba effect, where initially “hotter” states can thermalize anomalously fast, a phenomenon most cleanly observed within the chaotic phase. However, away from the chaotic regime, the system is distinguished by multiple crossings across connectivity in its distance from the thermal ensemble with time. Collectively, this work presents a broad characterization of chaos, providing insight beyond spectral analysis and practical indicators for benchmarking near-term quantum devices.
Disordered Systems and Neural Networks (cond-mat.dis-nn), High Energy Physics - Theory (hep-th), Quantum Physics (quant-ph)
Role of nanoparticle shape on the critical size for quasi-uniform ordering: from spheres to cubes through superballs
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-06 20:00 EDT
Iago López-Vázquez, David Serantes, Òscar Iglesias
The equilibrium magnetic states of single-domain magnetite nanoparticles (NPs) result from a subtle interplay between size, geometry, and magnetocrystalline anisotropy. In this work, we present a micromagnetic study of shape-controlled magnetite NPs using the superball geometry, which provides a continuous interpolation between spheres and cubes. By isolating the influence of shape, we analyze the transition from quasi-uniform (single-domain) to vortex-like states as particle size increases, revealing critical sizes that depend on the superball exponent. Our simulations show that faceted geometries promote the stabilization of vortex states at larger sizes, with marked distortions in the vortex core structure. The inclusion of cubic magnetocrystalline anisotropy, representative of magnetite, further lowers the critical size and introduces preferential alignment along the [111] easy axes. In contrast, the presence of slight particle elongation increases the critical size and induces another preferential alignment direction. These results demonstrate that even small deviations from sphericity or aspect ratio significantly alter the magnetic ordering and stability of equilibrium magnetic states.
Materials Science (cond-mat.mtrl-sci)
12 pages, 10 figures, submitted to J. Magn. Magn. Mater
Impeded Bloch Oscillation and Nonreciprocal Landau-Zener Tunneling of Bose-Einstein Quantum Droplets in Optical Lattices
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-08-06 20:00 EDT
Szu-Cheng Cheng, Yu-Wen Wang, Wen-Hsuan Kuan
We investigate the nonlinear Bloch dynamics and Landau-Zener tunneling of quantum droplets in optical lattices, where the interplay between mean-field repulsion and beyond-mean-field attraction from Lee-Huang-Yang corrections introduces a localization impedance that inhibits dynamical dispersion. This self-stabilizing mechanism is crucial to droplet mobility and nonlinear dephasing under external driving. In the deep-lattice regime, simulation in tight-binding reduction reveals breathing modes, self-trapping, and nonlinear Bloch oscillations. In the shallow-lattice regime, we reformulate the problem in momentum space and map the dynamics onto a nonlinear two-level model with time-dependent detuning. The adiabatic spectrum features looped bands and multiple fixed points, parallelly captured by the phase-space structure through a classical Josephson analogy. Applying Hamilton-Jacobi theory, we quantify the tunneling probabilities and demonstrate nonreciprocal Landau-Zener tunneling. The transition probability from the lower to upper band differs from that of the reverse process, even under the same sweeping protocol. This asymmetry arises from nonlinearly induced band gap modulation, highlighting rich dynamical behavior beyond the linear and adiabatic regimes.
Quantum Gases (cond-mat.quant-gas)
6 figures
Autonomous Inorganic Materials Discovery via Multi-Agent Physics-Aware Scientific Reasoning
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-06 20:00 EDT
Alireza Ghafarollahi, Markus J. Buehler
Conventional machine learning approaches accelerate inorganic materials design via accurate property prediction and targeted material generation, yet they operate as single-shot models limited by the latent knowledge baked into their training data. A central challenge lies in creating an intelligent system capable of autonomously executing the full inorganic materials discovery cycle, from ideation and planning to experimentation and iterative refinement. We introduce SparksMatter, a multi-agent AI model for automated inorganic materials design that addresses user queries by generating ideas, designing and executing experimental workflows, continuously evaluating and refining results, and ultimately proposing candidate materials that meet the target objectives. SparksMatter also critiques and improves its own responses, identifies research gaps and limitations, and suggests rigorous follow-up validation steps, including DFT calculations and experimental synthesis and characterization, embedded in a well-structured final report. The model’s performance is evaluated across case studies in thermoelectrics, semiconductors, and perovskite oxides materials design. The results demonstrate the capacity of SparksMatter to generate novel stable inorganic structures that target the user’s needs. Benchmarking against frontier models reveals that SparksMatter consistently achieves higher scores in relevance, novelty, and scientific rigor, with a significant improvement in novelty across multiple real-world design tasks as assessed by a blinded evaluator. These results demonstrate SparksMatter’s unique capacity to generate chemically valid, physically meaningful, and creative inorganic materials hypotheses beyond existing materials knowledge.
Materials Science (cond-mat.mtrl-sci), Disordered Systems and Neural Networks (cond-mat.dis-nn), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Artificial Intelligence (cs.AI), Machine Learning (cs.LG)
On the Pure States of the Replica Symmetry Breaking ansatz
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-08-06 20:00 EDT
We discuss the concept of Pure State of the Replica Symmetry Breaking ansatz in finite and infinite spin systems without averaging on the disorder, nor using replicas. Consider a system of n spins $ \sigma\in\Omega^{n}$ with the usual set $ \Omega=\left{ -1,1\right}$ of inner states and let $ G:,\Omega^{n}\rightarrow\left[0,1\right]$ a Gibbs measure on it of Hamiltonian $ \mathcal{H}$ (also non random). We interpret the pure states of a model $ \left(\Omega^{n},\mu\right)$ as disjoint subsets $ \Omega^{n}$ such that the conditional measures behaves like product measures as in usual mean field approximations. Starting from such definition we try to reinterpret the RSB scheme and define an approximated probability measure. We then apply our results to the Sherrington-Kirkpatrick model to obtain the Parisi formula.
Statistical Mechanics (cond-mat.stat-mech), Mathematical Physics (math-ph)
This paper has been written in the period 2015-2016 within the PTCC project (Coja-Oghlan) funded by the European Research Council. 19 pages. arXiv admin note: text overlap with arXiv:1610.03941
Structure Fluctuation Effects on Canonical-Nonlinear Thermodynamics
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-08-06 20:00 EDT
When we consider classical discrete systems under constant composition, their stable configuration in thermodynamic equilibrium can be typically obtained through the well-known canonica average phi. In configurational thermodynamics, phi as a map from many-body interatomic interaction to equilibrium configuration generally exhibits complicated nonlinearity, strongly depending on their underlying lattice. The connection between nonlinearity in phi (canonical nonlinearity) and the lattice has recently been amply investigated in terms of configurational geometry, leading to establishing its stochastic-thermodynamic treatment. The present work provides natural extention of the proposed treatment, explicitly including the effect of spatial fluctuation of the equilibrium configuration on thermodynamic property of the nonlinearity. We find that the fluctuation affects the upper-bound for the averaged nonlinearity disparity in multiple configurations, as an explicit and additional contribution from stochastic mutual information between focused coordination and its fluctuation, and an implicit contribution from changes in covariance matrix for density of states due to the fluctuation.
Statistical Mechanics (cond-mat.stat-mech)
4 pages, 2 figures
Self-assembled fluorescent nanodiamond layers for quantum imaging
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-08-06 20:00 EDT
Katherine Chea, Erin S. Grant, Kevin J. Rietwyk, Hiroshi Abe, Takeshi Ohshima, David A. Broadway, Jean-Philippe Tetienne, Gary Bryant, Philipp Reineck
The nitrogen-vacancy (NV) center in diamond is emerging as a powerful tool for imaging magnetic and electric signals at the microscale and below. However, most imaging demonstrations thus far have relied on costly, millimeter-sized bulk diamond substrates, which cannot be easily scaled or integrated with other materials. Here, we report a scalable method for fabricating NV-containing dense and homogenous fluorescent nanodiamond (FND) layers through electrostatic self-assembly and demonstrate the utility of the FND layers for magnetic imaging. We investigate the effect of FND concentration in suspension, substrate immersion time, and solvent pH on the FND density on the substrate. We identify optimized self-assembly conditions that maximize the FND density while minimizing aggregation. Using FND layers on a quartz substrate, we demonstrate magnetic field and magnetic noise imaging at the microscale, based on NV optically detected magnetic resonance magnetometry and T$ _1$ relaxometry, respectively. Our results provide a direction for the development of cost-effective and scalable FND layers and surface coatings. This paves the way for on-demand quantum sensing and imaging on a broad range of surfaces based on NV centers and other diamond quantum emitters.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Dichotomy of flat bands in the van der Waals ferromagnet Fe$_5$GeTe$_2$
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-08-06 20:00 EDT
Han Wu, Jianwei Huang, Chaowei Hu, Lei Chen, Yiqing Hao, Yue Shi, Paul Malinowski, Yucheng Guo, Bo Gyu Jang, Jian-Xin Zhu, Andrew F. May, Siqi Wang, Xiang Chen, Yaofeng Xie, Bin Gao, Yichen Zhang, Ziqin Yue, Zheng Ren, Makoto Hashimoto, Donghui Lu, Alexei Fedorov, Sung-Kwan Mo, Junichiro Kono, Yu He, Robert J. Birgeneau, Pengcheng Dai, Xiaodong Xu, Huibo Cao, Qimiao Si, Jiun-Haw Chu, Ming Yi
Quantum materials with bands of narrow bandwidth near the Fermi level represent a promising platform for exploring a diverse range of fascinating physical phenomena, as the high density of states within the small energy window often enables the emergence of many-body physics. On one hand, flat bands can arise from strong Coulomb interactions that localize atomic orbitals. On the other hand, quantum destructive interference can quench the electronic kinetic energy. Although both have a narrow bandwidth, the two types of flat bands should exhibit very distinct spectral properties arising from their distinctive origins. So far, the two types of flat bands have only been realized in very different material settings and chemical environments, preventing a direct comparison. Here, we report the observation of the two types of flat bands within the same material system–an above-room-temperature van der Waals ferromagnet, Fe$ _{5-x}$ GeTe$ _2$ , distinguishable by a switchable iron site order. The contrasting nature of the flat bands is also identified by the remarkably distinctive temperature-evolution of the spectral features, indicating that one arises from electron correlations in the Fe(1) site-disordered phase, while the other geometrical frustration in the Fe(1) site-ordered phase. Our results therefore provide a direct juxtaposition of the distinct formation mechanism of flat bands in quantum materials, and an avenue for understanding the distinctive roles flat bands play in the presence of magnetism, topology, and lattice geometrical frustration, utilizing sublattice ordering as a key control parameter.
Strongly Correlated Electrons (cond-mat.str-el)
The manuscript was submitted to a journal on June 12 2024
Observation of Embedded Topology in a Trivial Bulk via Projective Crystal Symmetry
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-08-06 20:00 EDT
Hau Tian Teo, Yang Long, Hong-yu Zou, Kailin Song, Haoran Xue, Yong Ge, Shou-qi Yuan, Hong-xiang Sun, Baile Zhang
Bulk-boundary correspondence is the foundational principle of topological physics, first established in the quantum Hall effect, where a $ D$ -dimensional topologically nontrivial bulk gives rise to $ (D-1)$ -dimensional boundary states. The advent of higher-order topology has generalized this principle to a hierarchical chain, enabling topological states to appear at $ (D-2)$ or even lower-dimensional boundaries. To date, all known realizations of topological systems must require a topologically nontrivial bulk to initiate the chain of action for bulk-boundary correspondence. Here, in an acoustic crystal platform, we experimentally demonstrate an exception to this paradigm–embedded topology in a trivial bulk–where the bulk-boundary correspondence originates from a trivial bulk. Rather than relying on global symmetries, we employ projective crystal symmetry, which induces nontrivial topology not at the outset in the $ D$ -dimensional bulk, but midway through the correspondence hierarchy in lower-dimensional boundaries. We further realize a three-dimensional system exhibiting embedded topology that supports zero-dimensional topological states, achieving the longest possible chain of action for such an unconventional bulk-boundary correspondence in physical space. Our work experimentally establishes a new form of bulk-boundary correspondence initiated from a trivial bulk, opening additional degrees of freedom for the design of robust topological devices.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
6 pages, 4 figures
Dielectric Substrate Dependence of Thermoelectric Transport in BLG-GaAs-BLG Heterostructures
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-08-06 20:00 EDT
Vo Van Tai, Truong Van Tuan, Tran Trong Tai, Le Tri Dat, Nguyen Duy Vy
We theoretically study the thermoelectric transport S in a double-layer bilayer graphene (BLG-GaAs-BLG) system on dielectric substrates (h-BN, Al2O3, HfO2). Electrons interact with GaAs acoustic phonons via both the deformation potential (acDP) and piezoelectric (acPE) scattering. Results show that piezoelectric scattering dominates the total transport, especially at low carrier density and high dielectric constant. Substrate dielectric constant significantly influences thermopower S, and the thermopower of the materials is in the order of HfO2 > Al2O3 > h-BN. When densities on two BLG layers are unequal, the contribution from acDP scattering Sd decreases (increases) at low (high) densities versus equal densities, while acPE scattering Sg remains stable, making S largely Sg-dependent. Increasing interlayer distance d enhances S, while higher temperature boosts Sd (notably at low densities) with minimal effect on Sg. These insights and substrate-dependent trends demonstrate substrate engineering as a key parameter for optimizing BLG thermoelectric devices
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
18 pages, 7 figures
Electronic ordering driven by flat band nesting in a van der Waals magnet Fe5GeTe2
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-08-06 20:00 EDT
Qiang Gao, Gabriele Berruto, Khanh Duy Nguyen, Chaowei Hu, Haoran Lin, Beomjoon Goh, Bo Gyu Jang, Xiaodong Xu, Peter Littlewood, Jiun-Haw Chu, Shuolong Yang
Solid-state systems with flat electronic bands have a theoretical propensity to form electronic orders such as superconductivity and charge-density waves. However, for many flat-band systems such as Kagome and Clover lattices, the flat bands do not naturally appear at the Fermi level, hence not driving the low-energy electronic ordering. Here we demonstrate the concurrent formation of flat bands at the Fermi level and a $ \sqrt{3} \times \sqrt{3}, R30^\circ$ charge order in a van der Waals magnet Fe5GeTe2 using high-resolution angle-resolved photoemission spectroscopy. This charge order is manifested by clear band structure folding below 100 K, yet the band folding is limited to 30 meV below the Fermi level where the flat bands reside. The nesting vector in the reciprocal space connects segments of Fermi surfaces where pronounced flat bands are discovered. Taken together with calculations of the Lindhard response function, our results establish Fe5GeTe2 as a model system where flat bands promote inter-band nesting and electronic ordering. The appearance of the flat band at the Fermi level is reminiscent of the Kondo lattice effect, yet we point out that the flat bands may originate from the abundance of vacancies in the Fe(1) sublattice, where the vacancies induce flat dispersions via destructive charge or spin interactions.
Strongly Correlated Electrons (cond-mat.str-el), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
15 pages, 5 figures
Observation of Anomalous Hall Effect in Bulk Single Crystals of n-type Cr-doped Sb${2}$Te${3}$ Magnetic Topological Insulator
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-06 20:00 EDT
Ali Sarikhani (1), Mathew Pollard (2), Jacob Cook (3), Sheng Qiu (2), Seng Huat Lee (2), Laleh Avazpour (2), Jack Crewse (2), William Fahrenholtz (4), Guang Bian (3), Yew San Hor (2) ((1) Material Research Center, Missouri University of Science and Technology, Rolla, MO, (2) Department of Physics, Missouri University of Science and Technology, Rolla, MO, (3) Department of Physics and Astronomy, University of Missouri, Columbia, MO, (4) Department of Materials Science and Engineering, Missouri University of Science and Technology, Rolla, MO)
The exploration of topological Dirac surface states is significant in the realms of condensed matter physics and future technological innovations. Among the materials garnering attention is Sb$ _{2}$ Te$ _{3}$ , a compound that theoretically exhibits topological insulating properties. However, its inherent p-type nature prevents the direct experimental verification of its Dirac surface state due to the Fermi level alignment with the valence band. In this study, by doping Cr atoms into Sb$ _{2}$ Te$ _{3}$ , n-type behavior is observed in the Hall resistance measurements. Remarkably, the Cr-doped Sb$ _{2}$ Te$ _{3}$ not only shows ferromagnetism with a high transition temperature of approximately 170 K but also exhibits an anomalous Hall effect (AHE). The Cr doping also allows for a controlled method for Fermi level tuning into the band gap. These properties spotlight its potential as an n-type magnetic topological insulator (MTI) as well as a material candidate for the quantum anomalous Hall effect (QAHE), opening new avenues for applications in spintronics and quantum devices.
Materials Science (cond-mat.mtrl-sci), Applied Physics (physics.app-ph)
The Open DAC 2025 Dataset for Sorbent Discovery in Direct Air Capture
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-06 20:00 EDT
Anuroop Sriram, Logan M. Brabson, Xiaohan Yu, Sihoon Choi, Kareem Abdelmaqsoud, Elias Moubarak, Pim de Haan, Sindy Löwe, Johann Brehmer, John R. Kitchin, Max Welling, C. Lawrence Zitnick, Zachary Ulissi, Andrew J. Medford, David S. Sholl
Identifying useful sorbent materials for direct air capture (DAC) from humid air remains a challenge. We present the Open DAC 2025 (ODAC25) dataset, a significant expansion and improvement upon ODAC23 (Sriram et al., ACS Central Science, 10 (2024) 923), comprising nearly 70 million DFT single-point calculations for CO$ _2$ , H$ _2$ O, N$ _2$ , and O$ _2$ adsorption in 15,000 MOFs. ODAC25 introduces chemical and configurational diversity through functionalized MOFs, high-energy GCMC-derived placements, and synthetically generated frameworks. ODAC25 also significantly improves upon the accuracy of DFT calculations and the treatment of flexible MOFs in ODAC23. Along with the dataset, we release new state-of-the-art machine-learned interatomic potentials trained on ODAC25 and evaluate them on adsorption energy and Henry’s law coefficient predictions.
Materials Science (cond-mat.mtrl-sci), Machine Learning (cs.LG)
An Analytic Model to Determine the Interstitial-Solute Energetics and Underlying Mechanism in Refractory High-Entropy Alloys
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-06 20:00 EDT
Qianxi Zhu, Wang Gao, Qing Jiang
The solution and diffusion of interstitial non-metallic solutes (INSs) like H, He, O, C, N, P, and S is common in refractory high-entropy alloys (RHEAs) and essentially controls the RHEAs properties. However, the disorder local chemical environments of RHEAs hinder the quantitative prediction of the stability and diffusivity of INSs and the understanding of the underlying mechanism. Based on the tight-binding models, we propose an analytic model for determining the stability and diffusivity of INSs in RHEAs, by approximating the bonding length between INSs and their neighbors with the atomic radius of the neighbors in elemental states. This predictive model identifies that the energetics of INSs depends linearly on the d-band width of their neighbors, with the slope determined by the valence of INSs. Our scheme provides an electronic-level understanding of INSs in RHEAs and explains key experimental observations, which can serve as an effective tool for designing advanced RHEAs.
Materials Science (cond-mat.mtrl-sci)
Topological band insulators without translational symmetry
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2025-08-06 20:00 EDT
Shuo Wang, Jing-Run Lin, Zheng-Wei Zuo
In the research of the topological band phases, the conventional wisdom is to start from the crystalline translational symmetry systems. Nevertheless, the translational symmetry is not always a necessary condition for the energy bands. Here we propose a systematic method of constructing the topological band insulators without translational symmetry in the amorphous systems. By way of the isospectral reduction approach from spectral graph theory, we reduce the structural-disordered systems formed by different multi-atomic cells into the isospectral effective periodic systems with the energy-dependent hoppings and potentials. We identify the topological band insulating phases with extended bulk states and topological in-gap edge states by the topological invariants of the reduced systems, density of states, and the commutation of the transfer matrix. In addition, when the building blocks of the two multi-atomic cells have different number of the lattice sites, our numerical calculations demonstrate that the existences of the flat band and the macroscopic bound states in the continuum in the amorphous systems. Our findings uncover a new arena for the exploration of the topological band states beyond translational symmetry systems paradigm.
Disordered Systems and Neural Networks (cond-mat.dis-nn), Quantum Gases (cond-mat.quant-gas)
7 pages, 5 figures, comments welcome
Quantum Bipolar Thermoelectricity
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-08-06 20:00 EDT
Filippo Antola, Giorgio De Simoni, Francesco Giazotto, Alessandro Braggio
Thermoelectricity usually originates from energy-dependent transport asymmetries. In this Letter, we explore a purely quantum thermoelectric effect rooted in the emission/absorption asymmetry of a low-temperature quantum bath. We propose a gap-asymmetric S-I-S’ superconducting tunnel junction in thermal equilibrium, coupled to a low-temperature electromagnetic environment, which develops a nonlinear quantum bipolar thermoelectric effect due to the dynamical Coulomb blockade. Key performance features are analyzed for realistic implementations.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Superconductivity (cond-mat.supr-con), Quantum Physics (quant-ph)
Organic altermagnets based in two-dimensional nanographene frameworks
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-08-06 20:00 EDT
Ricardo Ortiz, Karol Strutyński, Manuel Melle-Franco
Altermagnetism stands as a third type of collinear magnetic order, whose band structure combines a net zero magnetization with a non-relativistic spin-splitting caused by a broken time reversal symmetry. So far, the strategy to design platforms displaying altermagnetism has relied mostly on inorganic crystals with d-metals as spin centers, where a representative example is the two-dimensional square lattice with antiparallel D2h magnetic blocks related by a pi/2 rotation. Despite the fact that there is no strong requirement for the magnetic atoms to be metals, the construction of an altermagnetic framework with light elements like carbon is challenging due to symmetric constrictions. We show how it is possible to overcome this by including non-alternant rings in pi-conjugated nanographenes. More specifically, dibenzo[ef,kl]heptalene, an S = 1 pi-conjugated hydrocarbon consisting of a graph of two fused heptagons and hexagons, represents a suitable building block for an altermagnetic 2D crystal. In this work, we confirm this hypothesis with DFT calculations of the spin polarized band structure, presenting a spin compensated ground state with broken time reversal symmetry, and a d-wave symmetry of the first valence and conduction bands. Consistent results are obtained for covalent organic frameworks based on dibenzo[ef,kl]heptalene units connected by linkers, paving the way for the realization of organic altermagnetic materials.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Microscopic Theory of Light-Induced Coherent Phonons Mediated by Quantum Geometry
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-08-06 20:00 EDT
Jiaming Hu, Zhichao Guo, Wenbin Li, Hua Wang, Kai Chang
Light-induced coherent phonons provide a powerful platform for ultrafast control of material properties. However, the microscopic theory and quantum geometric nature of this phenomenon remain underexplored. Here, we develop a fully quantum-mechanical framework based on Feynman diagrams to systematically describe the generation of coherent phonons by light. We identify a dominant second-order, double-resonant process in noncentrosymmetric semiconductors that efficiently couples light to both electronic and phononic excitations. Crucially, we uncover the quantum geometric origin, encoded in the electron-phonon coupling (EPC) shift vector and the EPC quantum geometric tensor. Applying our theory to ferroelectric BaTiO$ _3$ and SnSe, we demonstrate the potential for light-induced modulation of ferroelectric polarization driven by coherent phonons. This work provides fundamental insights for designing efficient optical control strategies for both coherent phonons and ferroelectric polarization.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci), Strongly Correlated Electrons (cond-mat.str-el)
6 pages, 3 figures
Artificial Intelligence and Generative Models for Materials Discovery – A Review
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-06 20:00 EDT
Albertus Denny Handoko, Riko I Made
High throughput experimentation tools, machine learning (ML) methods, and open material databases are radically changing the way new materials are discovered. From the experimentally driven approach in the past, we are moving quickly towards the artificial intelligence (AI) driven approach, realizing the ‘inverse design’ capabilities that allow the discovery of new materials given the desired properties. This review aims to discuss different principles of AI-driven generative models that are applicable for materials discovery, including different materials representations available for this purpose. We will also highlight specific applications of generative models in designing new catalysts, semiconductors, polymers, or crystals while addressing challenges such as data scarcity, computational cost, interpretability, synthesizability, and dataset biases. Emerging approaches to overcome limitations and integrate AI with experimental workflows will be discussed, including multimodal models, physics informed architectures, and closed-loop discovery systems. This review aims to provide insights for researchers aiming to harness AI’s transformative potential in accelerating materials discovery for sustainability, healthcare, and energy innovation.
Materials Science (cond-mat.mtrl-sci), Artificial Intelligence (cs.AI), Applied Physics (physics.app-ph)
Review Article in the Thematic Issue on Artificial Intelligence for Materials Discovery in World Scientific Annual Review of Functional Materials
Multiscale Coupled Polarization and BKT Transitions in Tow-Dimensional Hybrid Organic-Inorganic Perovskites
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-06 20:00 EDT
We present an extended two-dimensional XY rotor model specifically designed to capture the polarization dynamics of hybrid organic-inorganic perovskite monolayers. This framework integrates nearest and next-nearest neighbor couplings, crystalline anisotropy inherent to perovskite lattice symmetries, external bias fields, and long-range dipolar interactions that are prominent in layered perovskite architectures. Through a combination of analytical coarse-graining and large-scale Monte Carlo simulations on 64\ast64 lattices, we identify two distinct thermodynamic regimes: a low-temperature quasi-ferroelectric state characterized by finite polarization and domain wall formation, and a higher-temperature Berezinskii-Kosterlitz-Thouless (BKT) crossover associated with vortex-antivortex unbinding and the suppression of long-range order. Our results reproduce key experimental signatures observed in quasi-two-dimensional perovskites, including dual peaks in dielectric susceptibility, enhanced vortex density near the transition, multistable polarization hysteresis under applied fields, and the scaling behavior of domain wall widths. This minimal yet realistic model provides a unifying perspective on how topological transitions and ferroelectric ordering coexist in layered perovskite systems, offering quantitative guidance for interpreting the emergent polar vortex lattices and complex phase behavior recently reported in hybrid perovskite thin films.
Materials Science (cond-mat.mtrl-sci)
6 pages, 2 figures
Berry Curvature of Low-Energy Excitons in Rhombohedral Graphene
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-08-06 20:00 EDT
Henry Davenport, Frank Schindler, Johannes Knolle
We investigate low energy excitons in rhombohedral pentalayer graphene encapsulated by hexagonal boron nitride (hBN/R5G/hBN), focusing on the regime at the experimental twist angle $ \theta = 0.77^\circ$ and with an applied electric field. We introduce a new low-energy two-band model of rhombohedral graphene that captures the band structure more accurately than previous models while keeping the number of parameters low. Using this model, we show that the centres of the exciton Wannier functions are displaced from the moiré unit cell origin by a quantised amount – they are instead localised at $ C_3$ -symmetric points on the boundary. We also find that the exciton shift is electrically tunable: by varying the electric field strength, the exciton Wannier centre can be exchanged between inequivalent corners of the moiré unit cell. Our results suggest the possibility of detecting excitonic corner or edge modes, as well as novel excitonic crystal defect responses in hBN/R5G/hBN. Lastly, we find that the excitons in hBN/R5G/hBN inherit excitonic Berry curvature from the underlying electronic bands, enriching their semiclassical transport properties. Our results position rhombohedral graphene as a compelling tunable platform for probing exciton topology in moiré materials.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
17 pages, 8 Figures
Machine learning potential for predicting thermal conductivity of θ-phase and amorphous Tantalum Nitride
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-06 20:00 EDT
Zhicheng Zong, Yangjun Qin, Jiahong Zhan, Haisheng Fang, Nuo Yang
Tantalum nitride (TaN) has attracted considerable attention due to its unique electronic and thermal properties, high thermal conductivity, and applications in electronic components. However, for the {\theta}-phase of TaN, significant discrepancies exist between previous experimental measurements and theoretical predictions. In this study, deep potential models for TaN in both the {\theta}-phase and amorphous phase were developed and employed in molecular dynamics simulations to investigate the thermal conductivities of bulk and nanofilms. The simulation results were compared with reported experimental and theoretical results, and the mechanism for differences were discussed. This study provides insights into the thermal transport mechanisms of TaN, offering guidance for its application in advanced electronic and thermal management devices.
Materials Science (cond-mat.mtrl-sci), Computational Physics (physics.comp-ph)
Thermal Metamaterials for Enhanced Non-Fourier Heat Transport
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-06 20:00 EDT
Harry Mclean, Francis Huw Davies, Ned Thaddeus Taylor, Steven Paul Hepplestone
The untapped potential of thermal metamaterials requires the simultaneous observation of both diffusive and wave-like heat propagation across multiple length scales that can only be realised through theories beyond Fourier. Here, we demonstrate that tailored material patterning significantly modifies heat transport dynamics with enhanced non-Fourier behaviour. By bridging phonon scattering mechanisms with macroscopic heat flux via a novel perturbation-theory approach, we derive the hyperbolic Cattaneo model directly from particle dynamics, establishing a direct link between relaxation time and phonon lifetimes. Our micro-scale patterned systems exhibit extended non-Fourier characteristics, where internal interfaces mediate wave-like energy propagation, diverging sharply from diffusive Fourier predictions. These results provide a unified framework connecting micro-scale interactions to macroscopic transport, resolving long-standing limitations of the Cattaneo model. This work underscores the transformative potential of thermal metamaterials for ultra-fast thermal management and nanoscale energy applications, laying a theoretical foundation for next-generation thermal technologies.
Materials Science (cond-mat.mtrl-sci)
Metallic glasses heterogeneous and time sensitive small scale plasticity probed through nanoindentation and machine learning clustering
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-06 20:00 EDT
S. Pomes, T. Suzuki, T. Enokizono, N. Adachi, M. Wakeda, T. Ohmura
Small-scale plasticity and creep behavior of a Zr-based BMG were investigated using nanoindentation. Four load functions, differing only in hold times of 0, 10, 30, and 60 seconds at peak load, were applied. Results indicate spatially heterogeneous and time-sensitive plastic behavior. Machine learning clustering, based on hardness and creep displacement, suggested three clusters. Statistical analysis of plastic energy distributions enabled identification of potential deformation mechanisms within the clusters.
Materials Science (cond-mat.mtrl-sci)
Stochastic systems with Bose-Hubbard interactions: Effects of bias on particles on a 1D lattice and random comb
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-08-06 20:00 EDT
Swastik Majumder, Mustansir Barma
Driven non-equilibrium lattice models have wide-ranging applications in contexts such as mass transport, traffic flow, and transport in biological systems. In this work, we investigate the steady-state properties of a one-dimensional lattice system that allows multiple particle occupancy on each site. The particles undergo stochastic nearest-neighbor jumps influenced by both a directional bias and on-site repulsive interactions. With periodic boundary conditions, we observe a non-monotonic dependence of inter-site correlation functions on the interaction strength. At large interaction strengths, the particle current exhibits a periodic dependence on density, accompanied by the formation of ordered stacks of particles. In contrast, with open boundary conditions, the system displays step-like density profiles reminiscent of those in tilted Bose-Hubbard systems, and a regime with a macroscopic number of empty sites followed by a steep parameter-dependent increase in density. Our results highlight how the interplay between drive, interaction, and boundary conditions leads to distinctive signatures on the current and density profiles in the steady state in different regimes.} {We also study the problem on a random comb, a simple model of a disordered system.
Statistical Mechanics (cond-mat.stat-mech)
14 pages, 15 figures
From Wye-Delta to Cross-Square Recursion Configurations in Graphene-Based Quantum Hall Arrays
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-08-06 20:00 EDT
Ngoc Thanh Mai Tran, Marta Musso, Dominick S. Scaletta, Wei-Chen Lin, Valery Ortiz Jimenez, Dean G. Jarrett, Massimo Ortolano, Curt A. Richter, Chi-Te Liang, David B. Newell, Albert F. Rigosi
In electrical metrology, the quantum Hall effect is accessed at the Landau level filling factor {\nu} = 2 plateau to define and disseminate the unit of electrical resistance (ohm). The robustness of the plateau is only exhibited at this Landau level filling factor and thus places a constraint on the quantized resistances that are accessible when constructing quantized Hall array resistance standards (QHARS) using epitaxial graphene on SiC. To overcome devices constrained by using Hall elements in series or in parallel, this work approaches the fabrication of a cross-square network configuration, which is similar to but departs slightly from conventional wye-delta designs and achieves significantly higher effective quantized resistance outputs. Furthermore, the use of pseudofractal-like recursion amplifies the ability to reach high resistances. QHARS devices designed as the ones here are shown to achieve an effective resistance of 55.81 M$ \Omega$ in one configuration and 27.61 G$ \Omega$ in another, with a hypothetically projected 317.95 T$ \Omega$ that could be accessed with more specialized equipment. Teraohmmeter measurements reveal the limits of conventional wet cryogenic systems due to resistance leakage. Ultimately, this work builds on the capability of realizing exceptionally high-value quantum resistance standards.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Investigation of Air Fluidization during Intruder Penetration in Sand
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-08-06 20:00 EDT
Bowen Wang, Yuxing Peng, Alvaro Vergara, Jordan H. Boyle, Raul Fuentes
Self-burrowing robots navigating through granular media benefit from airflow-assisted burrowing, which reduces penetration resistance. However, the mechanisms underlying airflow-granular interactions remain poorly understood. To address this knowledge gap, we employ a coupled computational fluid dynamics and discrete element method (CFD-DEM) approach, supplemented by experimental cone penetration tests (CPT) under varying airflow conditions, to investigate the effects of aeration on penetration resistance. Experimental results reveal a nonlinear relationship between penetration resistance reduction and depth, wherein resistance approaches near-zero values up to a critical depth, beyond which the effectiveness of fluidization diminishes. Simulations demonstrate that higher airflow rates enhance the mobilization of overlying grains, increasing the critical depth. A detailed meso- and micro-scale analysis of particle motion, contact forces, and fluid pressure fields reveals four distinct penetration stages: particle ejection and channel formation, channel sealing, channel refill, and final compaction. These findings contribute to a deeper understanding of granular aeration mechanisms and their implications for geotechnical engineering, excavation technologies, and the development of self-burrowing robotic systems.
Soft Condensed Matter (cond-mat.soft)
30 pages 10 figure
Engineering subgap states in superconductors by altermagnetism
New Submission | Superconductivity (cond-mat.supr-con) | 2025-08-06 20:00 EDT
Bo Lu, Phillip Mercebach, Pablo Burset, Keiji Yada, Jorge Cayao, Yukio Tanaka, Yuri Fukaya
We investigate the realization and control of subgap states by tailored altermagnetic fields on unconventional superconductors. When the symmetries of altermagnetism and unconventional superconductivity align, we demonstrate the emergence of bulk zero-energy flat bands, giving rise to a zero-bias conductance peak. The symmetry and strength of $ d$ - and $ g$ -wave altermagnets strongly affect the surface Andreev states from $ d$ -wave and chiral $ d$ - and $ p$ -wave superconductors. As a result, distinct types of subgap states are realized, including curved and flat bands, that can be detected by tunneling spectroscopy. Furthermore, we find that the altermagnetism-induced subgap states give rise to a large spin conductance at zero net magnetization which helps identify the strength of the underlying altermagnetism and superconductivity. Our results offer a solid route for designing and manipulating subgap states in superconducting systems, which can be useful for functionalizing superconducting spintronic devices.
Superconductivity (cond-mat.supr-con), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Magnon Spin Current Modulation through Site-Specific Doping in a Compensated Iron Garnet
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-08-06 20:00 EDT
Anna Merin Francis, P. B. S. Murthykrishnan, Ratnamay Kolay, Ramesh Nath, Sunil Nair
We report on the impact of manganese doping at the iron sites in Gadolinium Iron Garnet (GdIG, Gd$ _{3}$ Fe$ _{5}$ O$ {12}$ ), employing temperature-dependent spin Seebeck effect and ferromagnetic resonance measurements. Our findings reveal a clear shift in the magnetic compensation temperature ($ T{comp}$ ) in Mn-doped GdIG, with minimal changes observed in the magnetic and damping properties. Notably, the spin Seebeck signal strength was enhanced significantly with the Mn doping. This enhancement is attributed to an increased spin mixing conductance and modifications in the magnon spectra that strengthen exchange interactions, highlighting the material’s potential for room-temperature spintronic applications.
Strongly Correlated Electrons (cond-mat.str-el), Materials Science (cond-mat.mtrl-sci)
Model Accuracy and Data Heterogeneity Shape Uncertainty Quantification in Machine Learning Interatomic Potentials
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-06 20:00 EDT
Fei Shuang, Zixiong Wei, Kai Liu, Wei Gao, Poulumi Dey
Machine learning interatomic potentials (MLIPs) enable accurate atomistic modelling, but reliable uncertainty quantification (UQ) remains elusive. In this study, we investigate two UQ strategies, ensemble learning and D-optimality, within the atomic cluster expansion framework. It is revealed that higher model accuracy strengthens the correlation between predicted uncertainties and actual errors and improves novelty detection, with D-optimality yielding more conservative estimates. Both methods deliver well calibrated uncertainties on homogeneous training sets, yet they underpredict errors and exhibit reduced novelty sensitivity on heterogeneous datasets. To address this limitation, we introduce clustering-enhanced local D-optimality, which partitions configuration space into clusters during training and applies D-optimality within each cluster. This approach substantially improves the detection of novel atomic environments in heterogeneous datasets. Our findings clarify the roles of model fidelity and data heterogeneity in UQ performance and provide a practical route to robust active learning and adaptive sampling strategies for MLIP development.
Materials Science (cond-mat.mtrl-sci), Machine Learning (cs.LG)
Interstitial oxygen order and its competition with superconductivity in La$_2$PrNi$2$O${7+δ}$
New Submission | Superconductivity (cond-mat.supr-con) | 2025-08-06 20:00 EDT
Zehao Dong, Gang Wang, Ningning Wang, Wen-Han Dong, Lin Gu, Yong Xu, Jinguang Cheng, Zhen Chen, Yayu Wang
High-temperature superconductivity in bilayer nickelate La$ _3$ Ni$ _2$ O$ _7$ under pressure has attracted significant interest in condensed matter physics. While early samples exhibited limited superconducting volume fractions, Pr substitution for La enabled bulk superconductivity in polycrystals under pressure and enhanced transition temperatures in thin films at ambient pressure. Beyond rare-earth doping, moderate oxygen or ozone annealing improves superconductivity by mitigating oxygen vacancies, whereas high-pressure oxygen annealing leads to a trivial, non-superconducting metallic state across all pressure regimes. These findings highlight the need to elucidate both the individual and combined effects of Pr doping and oxygen stoichiometry in modulating superconductivity in bilayer nickelates. Here, using multislice electron ptychography and electron energy-loss spectroscopy, we investigate the structural and electronic properties of as-grown La$ _2$ PrNi$ _2$ O$ _7$ and high-pressure-oxygen-annealed La$ _2$ PrNi$ _2$ O$ _{7+\delta}$ polycrystals. We find that Pr dopants preferentially occupy outer La sites, effectively eliminating inner-apical oxygen vacancies and ensuring near-stoichiometry in as-grown La$ _2$ PrNi$ _2$ O$ _7$ that is bulk-superconducting under pressure. In contrast, high-pressure oxygen annealing induces a striped interstitial oxygen order, introducing quasi-1D lattice potentials and excess hole carriers into p-d hybridized orbitals, ultimately suppressing superconductivity. This behavior starkly contrasts with cuprate superconductors, where similar interstitial oxygen ordering enhances superconductivity instead. Our findings reveal a competition between striped interstitial oxygen order and superconductivity in bilayer nickelates, offering key insights into their distinct pairing mechanisms and providing a roadmap for designing more robust superconducting phases.
Superconductivity (cond-mat.supr-con), Materials Science (cond-mat.mtrl-sci), Strongly Correlated Electrons (cond-mat.str-el)
To appear in Nature Materials (2025)
Symmetry-breaking-induced topology in FeSe
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-06 20:00 EDT
Mikel García-Díez, Jonas B. Profe, Augustin Davignon, Steffen Backes, Roser Valentí, Maia G. Vergniory
FeSe has been one of the most intensively studied iron-based superconductors over the past two decades, exhibiting a wide range of phenomena such as unconventional superconductivity, nematic order, magnetism, orbital-selective correlations, and structural phase transitions. While topologically non-trivial phases have been identified in certain cases - such as Te-doped FeSe and monolayer FeSe - topology in bulk FeSe has largely remained unexplored. In this work, we propose a new route to realize topological phases directly in bulk FeSe. We demonstrate that breaking the in-plane $ C_4$ rotational symmetry, thereby lowering the crystal symmetry, can drive FeSe into a strong topological insulating phase. To support this, we perform density functional theory calculations and analyze the band structure using topological quantum chemistry and symmetry-based indicators. Our results show that both uniaxial strain and the structural transition to the orthorhombic low-temperature phase lead to non-trivial band topology. Moreover, incorporating electronic correlations through dynamical mean field theory reveals that the topological characteristics near the Fermi level remain robust, as the relevant bands experience only moderate renormalization. These findings highlight strain as a promising mechanism to induce topological phases in FeSe.
Materials Science (cond-mat.mtrl-sci), Strongly Correlated Electrons (cond-mat.str-el), Superconductivity (cond-mat.supr-con)
9 pages, 5 figures
Tentative demonstration of all-silicon photodetector: from near-infrared to mid-infrared
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-06 20:00 EDT
Jiaxin Ming, Yubing Du, Tongtong Xue, Yunyun Dai, Yabin Chen
Metastable silicon phases have attracted extensive attention these years, due to their fundamentally distinct photoelectric properties compared to the conventional diamond cubic (I) counterpart. Certain metastable phases, prepared via thermal heating method, can exhibit direct bandgap characteristics, significantly enhancing their light absorbance and quantum efficiency. Herein, we tentatively demonstrate an all-silicon photodetector working from near- to mid-infrared bands through precisely selective laser annealing strategy. We systematically investigated the optical properties and optoelectronic response of III/XII mixture, IV phase, and III/XII-I homojunctions. The obtained results reveal that III/XII composite and IV phase exhibit negative and positive photoconductivity, respectively. Furthermore, the established laser heating approach facilitates us to fabricate all-silicon homostructures with tunable photoconductive properties, such as III/XII-I and IV-I junctions. These findings can expand the potential applications of metastable semiconducting materials in optoelectronics and photodetectors.
Materials Science (cond-mat.mtrl-sci), Optics (physics.optics)
13 pages, 5 figures
Revealing Polymorph-Specific Transduction in WO$_3$ during Acetone Sensing
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-06 20:00 EDT
Matteo D’Andria, Meng Yin, Stefan Neuhauser, Vlasis G. Mavrantzas, Ying Chen, Ken Suzuki, Andreas T. Guentner
Polymorphs are distinct structural forms of the same compound and offer unique opportunities to tailor material properties without altering chemical composition. In particular, the polymorphs of WO$ _3$ have been widely explored for their molecular sensing performance; yet, the mechanistic aspects behind their different chemoresistive properties have remained elusive or poorly understood. Here, we highlight the energetic allocation of transferred charge as a critical aspect for chemoresistive response generation, providing a new perspective beyond more conventional net-transfer metrics, which are usually deployed to investigate gas-solid interactions. To this, we combined operando work function, chemisorption analysis, and in situ spectroscopy with density functional theory calculations on the example of acetone. Both gamma- and $ \varepsilon$ -WO$ _3$ exhibit comparable surface-level activation of acetone, mediated by electron-deficient, coordinatively unsaturated tungsten sites. However, only $ \varepsilon$ -WO$ _3$ stabilizes analyte-induced electronic states derived from W(5d) orbitals lying just below the conduction band - an energetically favourable region for conductivity modulation under operating conditions. While being associated with marginal work function shifts, these states reflect deeper subsurface electronic rearrangements that may underlie the $ \varepsilon$ -WO$ _3$ ‘s superior transduction efficiency despite similar receptor chemistry. Our results offer a new framework for rational transducer development rooted in intrinsic electronic structure.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Oxide Interface-Based Polymorphic Electronic Devices for Neuromorphic Computing
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2025-08-06 20:00 EDT
Soumen Pradhan (1), Kirill Miller (1), Fabian Hartmann (1), Merit Spring (2), Judith Gabel (2), Berengar Leikert (2), Silke Kuhn (1), Martin Kamp (1), Victor Lopez-Richard (3), Michael Sing (2), Ralph Claessen (2), Sven Höfling (1) ((1) Julius-Maximilians-Universität Würzburg, Physikalisches Institut and Würzburg-Dresden Cluster of Excellence <a href=”http://ct.qmat“ rel=”external noopener nofollow” class=”link-external link-http”>this http URL</a>, Lehrstuhl fürTechnische Physik, Germany, (2) Julius-Maximilians-Universität Würzburg, Physikalisches Institut and Würzburg-Dresden Cluster of Excellence <a href=”http://ct.qmat“ rel=”external noopener nofollow” class=”link-external link-http”>this http URL</a>, Experimentelle Physik 4, Germany, (3) Universidade Federal de São Carlos, Departamento de Física, Brazil)
Aside from recent advances in artificial intelligence (AI) models, specialized AI hardware is crucial to address large volumes of unstructured and dynamic data. Hardware-based AI, built on conventional complementary metal-oxidesemiconductor (CMOS)-technology, faces several critical challenges including scaling limitation of devices [1, 2], separation of computation and memory units [3] and most importantly, overall system energy efficiency [4]. While numerous materials with emergent functionalities have been proposed to overcome these limitations, scalability, reproducibility, and compatibility remain critical obstacles [5, 6]. Here, we demonstrate oxide-interface based polymorphic electronic devices with programmable transistor, memristor, and memcapacitor functionalities by manipulating the quasi-two-dimensional electron gas in LaAlO3/SrTiO3 heterostructures [7, 8] using lateral gates. A circuit utilizing two polymorphic functionalities of transistor and memcapacitor exhibits nonlinearity and short-term memory, enabling implementation in physical reservoir computing. An integrated circuit incorporating transistor and memristor functionalities is utilized for the transition from short- to long-term synaptic plasticity and for logic operations, along with in-situ logic output storage. The same circuit with advanced reconfigurable synaptic logic operations presents high-level multi-input decision-making tasks, such as patient-monitoring in healthcare applications. Our findings pave the way for oxide-based monolithic integrated circuits in a scalable, silicon compatible, energy efficient single platform, advancing both the polymorphic and neuromorphic computings.
Disordered Systems and Neural Networks (cond-mat.dis-nn), Materials Science (cond-mat.mtrl-sci)
20 pages, 5 figures
Out-of-equilibrium nonlinear model of thermoelectricity in superconducting tunnel junctions
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-08-06 20:00 EDT
Leonardo Lucchesi, Federico Paolucci
Thermoelectricity in superconducting tunnel junctions has always been studied under the hypothesis of equilibrium between the cold side and the thermal bath, usually in the linear regime. We define a more complete out-of-equilibrium nonlinear numerical model that reduces to the equilibrium linear model in the low-power limit. We find that the linear model does not correctly describe the behavior of superconducting tunnel junctions for parameters that are reasonable in practical experimental setups. Subsequently, we present the qualitative and quantitative differences between the models, discovering that for high power, the junction saturates and then inverts its behavior. Finally, we also clarify the difference between linear and nonlinear thermoelectricity and devise a new criterion to find nonlinear thermoelectricity in the parameter space.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Superconductivity (cond-mat.supr-con)
10 pages, 6 figures
Chirality transfer in lyotropic twist-bend nematics
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-08-06 20:00 EDT
Anna Ashkinazi, Hemani Chhabra, Anouar El Moumane, Maxime M. C. Tortora, Jonathan P. K. Doye
Using molecular simulations and classical density functional theory, we study the liquid-crystalline phase behaviour of a series of bent rod-like mesogens with a controlled degree of chirality introduced through a twist at the centre of the particle. In the achiral limit, isotropic, uniaxial nematic, twist-bend nematic and smectic phases form as the packing fraction increases. On introducing chirality, the symmetry between the right- and left-handed twist-bend phases is broken. The phase with the same-handedness as the particles quickly becomes overwhelmingly favoured as the magnitude of the particle twist is increased, because the particles are then able to better follow the helical director field lines in the twist-bend phase and pack more efficiently. By contrast, the cholesteric phase is predicted to have the opposite handedness to that of the particle due to the relatively weakly-twisted nature of the particles. That the cholesteric and twist-bend phases have opposite handedness illustrates the differences in the mechanisms of chirality transfer in the two phases. We also found that doping a system of achiral mesogens with a small fraction of chiral particles led to selection of the twist-bend phase with the same chirality as the particle.
Soft Condensed Matter (cond-mat.soft)
main text: 12 pages, 10 figures; Supplementary Material: 2 pages, 3 figures
Quantum Spin Hall Effect with Extended Topologically Protected Features in Altermangetic Multilayers
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-08-06 20:00 EDT
Zhiyu Chen, Fangyang Zhan, Da-Shuai Ma, Dong-Hui Xu, Rui Wang
Conventional topological classification theory dictates that time-reversal symmetry confines the quantum spin Hall (QSH) effect to a $ \mathbb{Z}_2$ classification, permitting only a single pair of gapless helical edge states. Here, we utilize the recently discovered altermagnetism to circumvent this fundamental constraint. We demonstrate the realization of a unique QSH phase possessing multiple pairs of gapless helical edge states in altermagnetic multilayers. This exotic QSH phase, characterized by a mirror-spin Chern number, emerges from the interplay of spin-orbit coupling and $ d$ -wave altermagnetic ordering. Moreover, using first-principles calculations, we identify altermagnetic Fe$ _2$ Se$ _2$ O multilayers as promising material candidates, in which the number of gapless helical edge states scales linearly with the number of layers, leading to a correspondingly large, exactly quantized, and experimentally accessible spin-Hall conductance. Our findings unveil a new mechanism for stabilizing multiple pairs of gapless helical edge states, significantly expanding the scope of QSH effects, and provide a blueprint for utilizing altermagnetism to engineer desired topological phases.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
6 pages, 4 figures
High-temperature and high-pressure study on columbite structured ZnNb2O6
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-08-06 20:00 EDT
A. Tyagi, P. Botella, A. B. Garg, J. Sanchez-Martin, D. Diaz-Anichtchenko, R. Turnbull, S. Anzellini, C. Popescu, D. Errandonea
High-temperature and high-pressure experiments were conducted on columbite-type ZnNb2O6, reaching temperatures up to 873 K at ambient pressure and pressures up to 30 GPa at ambient temperature, respectively. Through systematic analysis employing synchrotron powder X-ray diffraction and Raman spectroscopy, we examined the crystal structure and phonon behavior. Within the specified temperature range, the orthorhombic phase of ZnNb2O6 (space group: Pbcn) demonstrated notable phase stability, with a thermal expansion coefficient similar to that of isomorphic compounds. Notably, a reversible phase transition was observed under compression at 10 GPa, with diffraction experiments indicating a shift to a monoclinic structure (space group P2/a), which remained stable up to 30 GPa. Changes in Raman modes, lattice parameters, and the unit-cell volume were monitored. A significant 2.5% discontinuity in the unit-cell volume at the phase transition pressure from orthorhombic to monoclinic suggests a first-order phase transition. The bulk moduli of the orthorhombic and monoclinic phases were estimated as 165(7) GPa and 230(9) GPa, respectively- We also found that both phases exhibit an anisotropic response to pressure. Furthermore, first-principles calculations support consistently with experimental observations.
Materials Science (cond-mat.mtrl-sci)
34 pages, 17 figures, 4 tables
A noninvasive and nonadiabatic quantum Maxwell demon
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-08-06 20:00 EDT
A quantum mechanical Maxwell demon is proposed in a quantum dot setting. The demon avoids continuous-measurement induced decoherence by exploiting an undetailed charge detector. The control of coherent tunneling via Landau-Zener-Stückelberg-Majorana driving allows for efficient feedback operations with no work invested. The local violation of the second law achieves simultaneous power generation and cooling. We discuss the response current fluctuations, and the demon backaction deriving from failures, finding optimal performance in the nonadiabatic regime.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Quantum Physics (quant-ph)
4+ pages + references and suplementary material
Ising spin ladders of orthopyroxene CoGeO$_3$
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-08-06 20:00 EDT
Pavel A. Maksimov, Andrey F. Gubkin, Alexey V. Ushakov, Alexander I. Kolesnikov, Matthew S. Cook, Michael A. McGuire, Günther J. Redhammer, Andrey Podlesnyak, Sergey V. Streltsov
We present thermodynamic and spectroscopic measurements for an orthopyroxene CoGeO$ 3$ with magnetic Co$ ^{2+}$ ions that form quasi-one-dimensional ladders. We show that non-collinear magnetic order below $ T_N$ =32 K can be stabilized by a strong local easy-axis anisotropy of $ j\text{eff}=1/2$ moments, which is induced by ligand octahedra distortions. Extraction of a magnetic Hamiltonian from inelastic neutron scattering measurements supports this interpretation and allows us to establish an effective magnetic model. The resulting exchange Hamiltonian justifies CoGeO$ _3$ as a realization of an Ising spin ladder compound.
Strongly Correlated Electrons (cond-mat.str-el)
7+4 pages, 5+6 figures
Phonon Dynamics in Spherically-Curved Analog-Gravity Bose-Einstein Condensates
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-08-06 20:00 EDT
J. Austin Chunn, Ruotong Zhai, Daniel E. Sheehy
We study the low energy phonon dynamics of a Bose-Einstein condensate (BEC) with a density profile that is equivalent, via a coordinate transformation, to phonons traveling in a \lq\lq spherical\rq\rq\ curved spacetime that realizes the Friedman-Lemaître-Robertson-Walker (FLRW) metric. The metric of this BEC is characterized by its curvature $ \kappa$ and a time-depdendent scale factor $ a(t)$ , with an increase in the latter corresponding to an expansion of the analog FLRW universe. We study the propagation of classical phonons in such BECs, finding that a sudden change in the scale factor induces ripples in the wave motion. In addition, we study quantum phonon creation (or vacuum amplification) due to the scale-factor modification and quantify their entanglement.
Quantum Gases (cond-mat.quant-gas)
14 pages, 9 figures