Nature PhysicsPub Date : 2024-10-29DOI: 10.1038/s41567-024-02686-8
Padma Radhakrishnan, Ksenia S. Rabinovich, Alexander V. Boris, Katrin Fürsich, Matteo Minola, Georg Christiani, Gennady Logvenov, Bernhard Keimer, Eva Benckiser
{"title":"Imprinted atomic displacements drive spin–orbital order in a vanadate perovskite","authors":"Padma Radhakrishnan, Ksenia S. Rabinovich, Alexander V. Boris, Katrin Fürsich, Matteo Minola, Georg Christiani, Gennady Logvenov, Bernhard Keimer, Eva Benckiser","doi":"10.1038/s41567-024-02686-8","DOIUrl":"https://doi.org/10.1038/s41567-024-02686-8","url":null,"abstract":"<p>Perovskites with the generic composition <i>AB</i>O<sub>3</sub> exhibit an enormous variety of quantum states, such as orbital order, magnetism and superconductivity. Their flexible and comparatively simple structure allows for straightforward chemical substitution and cube-on-cube combination of different compounds in atomically sharp epitaxial heterostructures. Many of the diverse physical properties of perovskites are determined by small deviations from the ideal cubic perovskite structure, which are challenging to control. Here we show that directional imprinting of atomic displacements in the antiferromagnetic Mott insulator YVO<sub>3</sub> can be achieved by depositing epitaxial films on different facets of the same isostructural substrate. These facets were chosen such that other well-known control parameters, including lattice and polarity mismatch with the overlayer, remain nearly unchanged. We observe signatures of staggered orbital and magnetic order and demonstrate distinct spin–orbital ordering patterns on different facets. We attribute these results to the influence of specific octahedral rotation and cation displacement patterns, which are imprinted by the substrate facet, on the covalency of the bonds and the superexchange interactions in YVO<sub>3</sub>. Our results show that substrate-induced templating of lattice distortion patterns constitutes a pathway for materials design beyond established strain-engineering strategies.</p>","PeriodicalId":19100,"journal":{"name":"Nature Physics","volume":"63 1","pages":""},"PeriodicalIF":19.6,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142520167","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nature PhysicsPub Date : 2024-10-29DOI: 10.1038/s41567-024-02673-z
Ravi Kumar, Saurabh Kumar Srivastav, Ujjal Roy, Ujjawal Singhal, K. Watanabe, T. Taniguchi, Vibhor Singh, P. Roulleau, Anindya Das
{"title":"Absence of heat flow in ν = 0 quantum Hall ferromagnet in bilayer graphene","authors":"Ravi Kumar, Saurabh Kumar Srivastav, Ujjal Roy, Ujjawal Singhal, K. Watanabe, T. Taniguchi, Vibhor Singh, P. Roulleau, Anindya Das","doi":"10.1038/s41567-024-02673-z","DOIUrl":"10.1038/s41567-024-02673-z","url":null,"abstract":"The charge neutrality point of bilayer graphene, denoted as the ν = 0 state, manifests competing phases marked by spontaneous ordering of the spin, valley and layer degrees of freedom under external magnetic and electric fields. However, due to their electrically insulating nature, identifying these phases through electrical conductance measurements is a challenge. A recent theoretical proposal suggests that thermal transport measurements can detect these competing phases. Here we experimentally show that the bulk thermal transport of the ν = 0 state in bilayer graphene vanishes. This is in contrast to the theory, which predicts a finite thermal conductance in the ν = 0 state. By varying the external electric field and conducting temperature-dependent measurements, our results suggest that there are gapped collective excitations in the ν = 0 state. Our findings underscore the necessity for further investigations into the nature of the ν = 0 state. The ground state of charge-neutral bilayer graphene in a strong magnetic field is not fully determined. Now thermal transport measurements show an absence of heat flow through that state, suggesting that its collective excitations could be gapped.","PeriodicalId":19100,"journal":{"name":"Nature Physics","volume":"20 12","pages":"1941-1947"},"PeriodicalIF":17.6,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142520165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nature PhysicsPub Date : 2024-10-28DOI: 10.1038/s41567-024-02666-y
Matthias Willensdorfer, Verena Mitterauer, Matthias Hoelzl, Wolfgang Suttrop, Mark Cianciosa, Mike Dunne, Rainer Fischer, Nils Leuthold, Jonas Puchmayr, Oleg Samoylov, Guillermo Suárez López, Daniel Wendler, the ASDEX Upgrade Team
{"title":"Observation of magnetic islands in tokamak plasmas during the suppression of edge-localized modes","authors":"Matthias Willensdorfer, Verena Mitterauer, Matthias Hoelzl, Wolfgang Suttrop, Mark Cianciosa, Mike Dunne, Rainer Fischer, Nils Leuthold, Jonas Puchmayr, Oleg Samoylov, Guillermo Suárez López, Daniel Wendler, the ASDEX Upgrade Team","doi":"10.1038/s41567-024-02666-y","DOIUrl":"10.1038/s41567-024-02666-y","url":null,"abstract":"In tokamaks, a leading platform for fusion energy, periodic filamentary plasma eruptions known as edge-localized modes occur in plasmas with high-energy confinement and steep pressure profiles at the plasma edge. These edge-localized modes could damage the tokamak wall but can be suppressed using small three-dimensional magnetic perturbations. Here we demonstrate that these magnetic perturbations can change the magnetic topology just inside the steep gradient region of the plasma edge. We identify signatures of a magnetic island, and their observation is linked to the suppression of edge-localized modes. We compare high-resolution measurements of perturbed magnetic surfaces with predictions from ideal magnetohydrodynamic theory where the magnetic topology is preserved. Although ideal magnetohydrodynamics adequately describes the measurements in plasmas exhibiting edge-localized modes, it proves insufficient for plasmas where these modes are suppressed. Nonlinear resistive magnetohydrodynamic modelling supports this observation. Our study experimentally confirms the predicted role of magnetic islands in inhibiting the occurrence of edge-localized modes. This will be beneficial for physics-based predictions in future fusion devices to control these modes. The suppression of edge-localized modes in tokamak plasmas is crucial to prevent them from damaging the walls of the chamber. Now experiments confirm the role that magnetic islands play in suppressing these detrimental modes.","PeriodicalId":19100,"journal":{"name":"Nature Physics","volume":"20 12","pages":"1980-1988"},"PeriodicalIF":17.6,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41567-024-02666-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142519251","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nature PhysicsPub Date : 2024-10-28DOI: 10.1038/s41567-024-02687-7
Shashi Thutupalli
{"title":"The cost of cellular patterns","authors":"Shashi Thutupalli","doi":"10.1038/s41567-024-02687-7","DOIUrl":"10.1038/s41567-024-02687-7","url":null,"abstract":"The cell cortex consists of a chemical and a mechanical subsystem, but how energy is allocated between them is unknown. Now, measurements of the entropy production rate have revealed what determines the cell cortex’s energy budget.","PeriodicalId":19100,"journal":{"name":"Nature Physics","volume":"20 11","pages":"1704-1705"},"PeriodicalIF":17.6,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142519253","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nature PhysicsPub Date : 2024-10-28DOI: 10.1038/s41567-024-02677-9
Mingjie Xin, Wui Seng Leong, Zilong Chen, Yu Wang, Shau-Yu Lan
{"title":"Fast quantum gas formation via electromagnetically induced transparency cooling","authors":"Mingjie Xin, Wui Seng Leong, Zilong Chen, Yu Wang, Shau-Yu Lan","doi":"10.1038/s41567-024-02677-9","DOIUrl":"https://doi.org/10.1038/s41567-024-02677-9","url":null,"abstract":"<p>Ultracold quantum gases play a pivotal role in many-body physics, quantum sensing and quantum simulation. Over time, methods such as evaporative cooling in bulk ensembles and precision laser-cooling have been employed to effectively achieve quantum degeneracy in atomic gases. A simpler and more rapid way to form quantum gases would, thus, hold considerable promise in advancing the field. Here, we report the creation of a quantum gas by cooling individual rubidium atoms pinned in a three-dimensional optical lattice using electromagnetically induced transparency and adiabatic expansion. After just 10 ms of cooling, we verified the phase transition from a thermal to a quantum gas by adiabatically transferring the atoms to optical dipole traps. We observed the collapse of atoms in three-dimensional traps, a distinctive hallmark of a quantum gas with negative scattering length. Additionally, in a one-dimensional optical trap, we observed the emergence of a stable and strongly correlated quantum gas. Our results introduce a versatile and fast approach to achieving quantum degenerate gases with minimal time and resource requirements.</p>","PeriodicalId":19100,"journal":{"name":"Nature Physics","volume":"18 1","pages":""},"PeriodicalIF":19.6,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142519264","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nature PhysicsPub Date : 2024-10-22DOI: 10.1038/s41567-024-02675-x
Man Cheng, Qifeng Hu, Yuqiang Huang, Chenyang Ding, Xiao-Bin Qiang, Chenqiang Hua, Hanyan Fang, Jiong Lu, Yuxuan Peng, Jinbo Yang, Chuanying Xi, Li Pi, Kenji Watanabe, Takashi Taniguchi, Hai-Zhou Lu, Kostya S. Novoselov, Yunhao Lu, Yi Zheng
{"title":"Quantum tunnelling with tunable spin geometric phases in van der Waals antiferromagnets","authors":"Man Cheng, Qifeng Hu, Yuqiang Huang, Chenyang Ding, Xiao-Bin Qiang, Chenqiang Hua, Hanyan Fang, Jiong Lu, Yuxuan Peng, Jinbo Yang, Chuanying Xi, Li Pi, Kenji Watanabe, Takashi Taniguchi, Hai-Zhou Lu, Kostya S. Novoselov, Yunhao Lu, Yi Zheng","doi":"10.1038/s41567-024-02675-x","DOIUrl":"10.1038/s41567-024-02675-x","url":null,"abstract":"Electron tunnelling in solids, a fundamental quantum phenomenon, lays the foundation for various modern technologies. The emergence of van der Waals magnets presents opportunities for discovering unconventional tunnelling phenomena. Here, we demonstrate quantum tunnelling with tunable spin geometric phases in a multilayer van der Waals antiferromagnet CrPS4. The spin geometric phase of electron tunnelling is controlled by magnetic-field-dependent metamagnetic phase transitions. The square lattice of a CrPS4 monolayer causes strong t2g-orbital delocalization near the conduction band minimum. This creates a one-dimensional spin system with reversed energy ordering between the t2g and eg spin channels, which prohibits both intralayer spin relaxation by means of collective magnon excitations and interlayer spin hopping between the t2g and eg spin channels. The resulting coherent electron transmission shows pronounced tunnel magnetoresistance oscillations, manifesting quantum interference of cyclic quantum evolutions of individual electron Bloch waves by means of the time-reversal symmetrical tunnelling loops. Our results suggest the appearance of Aharonov–Anandan phases that originate from the non-adiabatic generalization of the Berry’s phase. It is difficult to control the geometric phase of particles as they undergo quantum tunnelling. Now tuning of the geometric phase of electron spin is demonstrated in tunnelling in a multilayer van der Waals antiferromagnet.","PeriodicalId":19100,"journal":{"name":"Nature Physics","volume":"20 12","pages":"1973-1979"},"PeriodicalIF":17.6,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142452600","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nature PhysicsPub Date : 2024-10-18DOI: 10.1038/s41567-024-02680-0
Alexandra Gade, Brenden Longfellow, Robert V. F. Janssens, Duc D. Dao, Frédéric Nowacki, Jeffrey A. Tostevin, Akaa D. Ayangeakaa, Marshall J. Basson, Christopher M. Campbell, Michael P. Carpenter, Joseph Chung-Jung, Heather L. Crawford, Benjamin P. Crider, Peter Farris, Stephen Gillespie, Ava M. Hill, Silvia M. Lenzi, Shumpei Noji, Jorge Pereira, Carlotta Porzio, Alfredo Poves, Elizabeth Rubino, Dirk Weisshaar
{"title":"In-beam spectroscopy reveals competing nuclear shapes in the rare isotope 62Cr","authors":"Alexandra Gade, Brenden Longfellow, Robert V. F. Janssens, Duc D. Dao, Frédéric Nowacki, Jeffrey A. Tostevin, Akaa D. Ayangeakaa, Marshall J. Basson, Christopher M. Campbell, Michael P. Carpenter, Joseph Chung-Jung, Heather L. Crawford, Benjamin P. Crider, Peter Farris, Stephen Gillespie, Ava M. Hill, Silvia M. Lenzi, Shumpei Noji, Jorge Pereira, Carlotta Porzio, Alfredo Poves, Elizabeth Rubino, Dirk Weisshaar","doi":"10.1038/s41567-024-02680-0","DOIUrl":"https://doi.org/10.1038/s41567-024-02680-0","url":null,"abstract":"<p>In recent decades, rare-isotope facilities have enabled the study of short-lived, neutron-rich nuclei. Their measured properties indicate that shell structure changes in the regime of unbalanced neutron-to-proton ratios compared with that of stable nuclei. In the so-called islands of inversion in the nuclear chart—around the neutron-rich nuclei <sup>32</sup>Mg, <sup>42</sup>Si and <sup>64</sup>Cr, for example—the textbook shell model predicts spherical shapes due to the respective magic neutron numbers of 20, 28 and 40 of these nuclei. However, nuclei in these regions turn out to be deformed in their ground states. Another hallmark of these islands is shape coexistence, where a nucleus assumes different shapes with excitation energy. Here we present evidence for this phenomenon from the observation of an excited 0<sup>+</sup> state in <sup>62</sup>Cr, two neutrons away from the heart of the island of inversion around neutron number <i>N</i> = 40. We use large-scale shell-model calculations to interpret the results, and we report extrapolations for the doubly magic nucleus <sup>60</sup>Ca.</p>","PeriodicalId":19100,"journal":{"name":"Nature Physics","volume":"43 1","pages":""},"PeriodicalIF":19.6,"publicationDate":"2024-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142448253","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nature PhysicsPub Date : 2024-10-14DOI: 10.1038/s41567-024-02668-w
Kwangrae Kim, Hyun-Woo J. Kim, Seunghyeok Ha, Hoon Kim, Jin-Kwang Kim, Jaehwon Kim, Junyoung Kwon, Jihoon Seol, Saegyeol Jung, Changyoung Kim, Daisuke Ishikawa, Taishun Manjo, Hiroshi Fukui, Alfred Q. R. Baron, Ahmet Alatas, Ayman Said, Michael Merz, Matthieu Le Tacon, Jin Mo Bok, Ki-Seok Kim, B. J. Kim
{"title":"Origin of the chiral charge density wave in transition-metal dichalcogenide","authors":"Kwangrae Kim, Hyun-Woo J. Kim, Seunghyeok Ha, Hoon Kim, Jin-Kwang Kim, Jaehwon Kim, Junyoung Kwon, Jihoon Seol, Saegyeol Jung, Changyoung Kim, Daisuke Ishikawa, Taishun Manjo, Hiroshi Fukui, Alfred Q. R. Baron, Ahmet Alatas, Ayman Said, Michael Merz, Matthieu Le Tacon, Jin Mo Bok, Ki-Seok Kim, B. J. Kim","doi":"10.1038/s41567-024-02668-w","DOIUrl":"10.1038/s41567-024-02668-w","url":null,"abstract":"Chirality refers to a structure that lacks mirror symmetry. It can be observed in a wide range of platforms, from subatomic particles and molecules to living organisms. However, the underlying mechanisms that give rise to chirality in condensed matter systems have been a subject of considerable interest. Here we elucidate the mechanism of chiral charge density wave formation in the transition-metal dichalcogenide 1T-TiSe2. Based on symmetry analysis, we demonstrate that charge density modulations and ionic displacements follow distinct irreducible representations of the space group, despite exhibiting similar wave vectors and a strong coupling. This charge-lattice symmetry frustration induces lattice distortions that further break all symmetries that are not common to both sectors. This ultimately gives rise to chirality. Our theory is verified using Raman spectroscopy and inelastic X-ray scattering. The mechanism of chiral symmetry breaking in condensed matter systems is not well understood. Now charge-lattice symmetry frustration has been shown to be a key factor governing chirality in a charge density wave of 1T-TiSe2.","PeriodicalId":19100,"journal":{"name":"Nature Physics","volume":"20 12","pages":"1919-1926"},"PeriodicalIF":17.6,"publicationDate":"2024-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142431128","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nature PhysicsPub Date : 2024-10-14DOI: 10.1038/s41567-024-02664-0
Yuchen Li, Tian-Gang Zhou, Ze Wu, Pai Peng, Shengyu Zhang, Riqiang Fu, Ren Zhang, Wei Zheng, Pengfei Zhang, Hui Zhai, Xinhua Peng, Jiangfeng Du
{"title":"Emergent universal quench dynamics in randomly interacting spin models","authors":"Yuchen Li, Tian-Gang Zhou, Ze Wu, Pai Peng, Shengyu Zhang, Riqiang Fu, Ren Zhang, Wei Zheng, Pengfei Zhang, Hui Zhai, Xinhua Peng, Jiangfeng Du","doi":"10.1038/s41567-024-02664-0","DOIUrl":"10.1038/s41567-024-02664-0","url":null,"abstract":"Universal behaviour often emerges in the low-energy equilibrium physics of quantum many-body systems, despite their microscopic differences. Recently, there has been a growing interest in studying the far-from-equilibrium dynamics of quantum many-body systems. Such dynamics usually involve highly excited states beyond the traditional low-energy theory description. Whether universality can also emerge in such non-equilibrium dynamics is the subject of current research. Here, we report the experimental observation of universal dynamics by monitoring the spin depolarization process in a solid-state nuclear magnetic resonance system, described by an ensemble of randomly interacting spins. The spin depolarization can be related to temporal spin–spin correlation functions at high temperatures. We discover that these correlation functions obey a universal functional form. This finding helps us identify the dominant interacting processes in the spin depolarization dynamics that lead to universality. Our observation demonstrates the existence of universality even in non-equilibrium dynamics at high temperatures, thereby complementing the well-established universality in low-energy physics. Universal properties have previously been observed mostly in the equilibrium physics of many-body systems in the low-energy and low-temperature regime. Now universality is observed at high temperature in the spin dynamics of a solid-state nuclear magnetic resonance system.","PeriodicalId":19100,"journal":{"name":"Nature Physics","volume":"20 12","pages":"1966-1972"},"PeriodicalIF":17.6,"publicationDate":"2024-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142431124","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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