Nature Physics最新文献

{"title":"Effect of energetic ions on edge-localized modes in tokamak plasmas","authors":"J. Dominguez-Palacios, S. Futatani, M. Garcia-Munoz, A. Jansen van Vuuren, E. Viezzer, J. Gonzalez-Martin, M. Toscano-Jimenez, P. Oyola, Y. Todo, Y. Suzuki, L. Sanchis, J. Rueda-Rueda, J. Galdon-Quiroga, J. Hidalgo-Salaverri, H. Chen, J. F. Rivero-Rodriguez, L. Velarde, the ASDEX Upgrade Team, the EuroFUSION MST1 Team","doi":"10.1038/s41567-024-02715-6","DOIUrl":"10.1038/s41567-024-02715-6","url":null,"abstract":"The most efficient and promising operational regime for the International Thermonuclear Experimental Reactor tokamak is the high-confinement mode. In this regime, however, periodic relaxations of the plasma edge can occur. These edge-localized modes pose a threat to the integrity of the fusion device. Here we reveal the strong impact of energetic ions on the spatio-temporal structure of edge-localized modes in tokamaks using nonlinear hybrid kinetic–magnetohydrodynamic simulations. A resonant interaction between the fast ions at the plasma edge and the electromagnetic perturbations from the edge-localized mode leads to an energy and momentum exchange. Energetic ions modify, for example, the amplitude, frequency spectrum and crash timing of edge-localized modes. The simulations reproduce some observations that feature abrupt and large edge-localized mode crashes. The results indicate that, in the International Thermonuclear Experimental Reactor, a strong interaction between the fusion-born alpha particles and ions from neutral beam injection, a main heating and fast particle source, is expected with predicted edge-localized mode perturbations. This work advances the understanding of the physics underlying edge-localized mode crashes in the presence of energetic particles and highlights the importance of including energetic ion kinetic effects in the optimization of edge-localized mode control techniques and regimes that are free of such modes. Edge-localized plasma modes in a tokamak can damage its innermost wall. Simulations now show that fast ions can modify the spatio-temporal structure of these modes. These effects need to be considered in the optimization of control techniques.","PeriodicalId":19100,"journal":{"name":"Nature Physics","volume":"21 1","pages":"43-51"},"PeriodicalIF":17.6,"publicationDate":"2025-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41567-024-02715-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142929334","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}

{"title":"A solid-state electrolyte with liquid-like vibrational character","authors":"Claudio Cazorla","doi":"10.1038/s41567-024-02698-4","DOIUrl":"10.1038/s41567-024-02698-4","url":null,"abstract":"Solid-state electrolytes with high ionic conductivity are promising candidates for battery applications. Experiments in one of these materials now reveal a mechanism that mediates ionic diffusivity and mirrors the vibrational properties of liquids.","PeriodicalId":19100,"journal":{"name":"Nature Physics","volume":"21 1","pages":"11-12"},"PeriodicalIF":17.6,"publicationDate":"2025-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142929332","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}

{"title":"First-order quantum breakdown of superconductivity in an amorphous superconductor","authors":"Thibault Charpentier, David Perconte, Sébastien Léger, Kazi Rafsanjani Amin, Florent Blondelle, Frédéric Gay, Olivier Buisson, Lev Ioffe, Anton Khvalyuk, Igor Poboiko, Mikhail Feigel’man, Nicolas Roch, Benjamin Sacépé","doi":"10.1038/s41567-024-02713-8","DOIUrl":"10.1038/s41567-024-02713-8","url":null,"abstract":"Continuous quantum phase transitions are widely assumed and frequently observed in various systems of quantum particles or spins. Their characteristic trait is a second-order, gradual suppression of the order parameter as the quantum critical point is approached. The localization of Cooper pairs in disordered superconductors and the resulting breakdown of superconductivity have long stood as a prototypical example. Here we show a departure from this paradigm, in which a discontinuous first-order quantum phase transition is tuned by disorder. We measure the plasmon spectrum in superconducting microwave resonators on amorphous superconducting films of indium oxide to provide evidence for a marked jump in both the zero-temperature superfluid stiffness and the transition temperature at the critical disorder. This discontinuous transition sheds light on the role of repulsive interactions between Cooper pairs and the subsequent competition between superconductivity and insulating Cooper-pair glass. Furthermore, we show that the critical temperature of the films no longer relates to the pairing amplitude but aligns with the superfluid stiffness, consistent with the pseudogap regime of preformed Cooper pairs. Our findings raise fundamental new questions about the role of disorder in quantum phase transitions and carry implications for superinductances in quantum circuits. A first-order, disorder-driven, superconductor–insulator phase transition is demonstrated. This is in contrast with the usually observed second-order transition and highlights the role of Coulomb interactions between preformed Cooper pairs.","PeriodicalId":19100,"journal":{"name":"Nature Physics","volume":"21 1","pages":"104-109"},"PeriodicalIF":17.6,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142917009","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}

{"title":"Large quantum fluctuations observed in strongly interacting bosons","authors":"","doi":"10.1038/s41567-024-02701-y","DOIUrl":"10.1038/s41567-024-02701-y","url":null,"abstract":"Among weakly interacting bosons, quantum fluctuations are akin to those of harmonic oscillators, and they manifest themselves through positive correlations between particles of opposite momenta. A quantum-gas experiment reveals that, by cranking up the interactions, these correlations are suppressed, and hence that quantum fluctuations become strong and anharmonic.","PeriodicalId":19100,"journal":{"name":"Nature Physics","volume":"21 1","pages":"19-20"},"PeriodicalIF":17.6,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142917084","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}

{"title":"Suppression of Bogoliubov momentum pairing and emergence of non-Gaussian correlations in ultracold interacting Bose gases","authors":"Jan-Philipp Bureik, Gaétan Hercé, Maxime Allemand, Antoine Tenart, Tommaso Roscilde, David Clément","doi":"10.1038/s41567-024-02700-z","DOIUrl":"10.1038/s41567-024-02700-z","url":null,"abstract":"Strongly correlated quantum matter, such as interacting electron systems or interacting quantum fluids, exhibits properties that defy explanation in terms of linear fluctuations and free quasiparticles. In these systems, quantum fluctuations are large and generically display non-Gaussian statistics—a property captured only by inspecting high-order correlations, whose quantitative reconstruction presents a challenge for both experiments and theory. A prime example of correlated quantum matter is the strongly interacting Bose fluid, realized first in superfluid helium and, more recently, in ultracold atoms. Here, we experimentally study interacting Bose gases from the weakly to the strongly interacting regime through single-atom-resolved correlations in momentum space. We find that the Bogoliubov pairing among modes of opposite momenta, characteristic of the weakly interacting regime, is suppressed as interactions grow. This departure from the predictions of Bogoliubov theory marks the onset of the strongly correlated regime, as confirmed by numerical simulations that highlight the role of nonlinear quantum fluctuations in our system. Furthermore, our measurements reveal a non-zero four-operator cumulant at even stronger interactions, which is a direct signature of non-Gaussian correlations. These results shed light on the emergence and physical origin of non-Gaussian correlations in ensembles of interacting bosons. In strongly correlated systems, weak interactions can lead to the formation of correlated pairs of bosons with opposite momenta. Now, an experiment on ultracold bosons shows the breakdown of this effect in the strong interaction regime.","PeriodicalId":19100,"journal":{"name":"Nature Physics","volume":"21 1","pages":"57-62"},"PeriodicalIF":17.6,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142917010","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}

{"title":"Emergent interaction-driven elliptic flow of few fermionic atoms","authors":"Sandra Brandstetter, Philipp Lunt, Carl Heintze, Giuliano Giacalone, Lars H. Heyen, Maciej Gałka, Keerthan Subramanian, Marvin Holten, Philipp M. Preiss, Stefan Floerchinger, Selim Jochim","doi":"10.1038/s41567-024-02705-8","DOIUrl":"10.1038/s41567-024-02705-8","url":null,"abstract":"Hydrodynamics is a successful framework for effectively describing the dynamics of complex many-body systems, ranging from subnuclear to cosmological scales. It applies coarse-grained assumptions about the microscopic constituents of a system to define macroscopic fluid cells, which are large compared to the interparticle spacing and mean free path. In high-energy heavy-ion collisions, hydrodynamic behaviour is inferred from the observation of elliptic flow, which is the elliptical deformation of the particle momentum distribution. Here we demonstrate the emergence of elliptic flow in a mesoscopic system with a few strongly interacting ultracold atoms. In our system, a hydrodynamic description is a priori not applicable, as all relevant length scales—the system size, the interparticle spacing and the mean free path—are comparable. The single-particle resolution and the deterministic control over the number of particles and interaction strength in our experiment allow us to explore the boundaries between a microscopic description and a hydrodynamic framework, and we show that elliptic flow appears as an interaction-driven effect. Our results demonstrate the emergence of collective behaviour in a regime where hydrodynamics is not usually applicable. Hydrodynamics can describe the collective behaviour of many-body systems when all the relevant length scales are separable. Now, an experiment with ultracold atoms shows signatures of hydrodynamic behaviour in a regime where length scales are comparable.","PeriodicalId":19100,"journal":{"name":"Nature Physics","volume":"21 1","pages":"52-56"},"PeriodicalIF":17.6,"publicationDate":"2025-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142911547","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}

{"title":"Fluids constructed atom by atom","authors":"Vir B. Bulchandani","doi":"10.1038/s41567-024-02646-2","DOIUrl":"10.1038/s41567-024-02646-2","url":null,"abstract":"Macroscopic fluid dynamics is usually thought to emerge from vast numbers of microscopic particles. Now, fluid-like behaviour has been observed in systems of startlingly few atoms.","PeriodicalId":19100,"journal":{"name":"Nature Physics","volume":"21 1","pages":"7-8"},"PeriodicalIF":17.6,"publicationDate":"2025-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142911546","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}

{"title":"Spinning into new regimes","authors":"Kazumasa A. Takeuchi","doi":"10.1038/s41567-024-02730-7","DOIUrl":"10.1038/s41567-024-02730-7","url":null,"abstract":"Collectives of self-driven particles display a plethora of behaviours that are gradually being discovered. Experiments with rotating particles in intermediate Reynolds flow now harness a mostly unexplored inertial regime for synthetic active matter.","PeriodicalId":19100,"journal":{"name":"Nature Physics","volume":"21 1","pages":"15-16"},"PeriodicalIF":17.6,"publicationDate":"2025-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142911545","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}

{"title":"Activity-induced annealing leads to a ductile-to-brittle transition in amorphous solids","authors":"Rishabh Sharma, Smarajit Karmakar","doi":"10.1038/s41567-024-02724-5","DOIUrl":"10.1038/s41567-024-02724-5","url":null,"abstract":"Active glasses are dense and disordered systems consisting of motile particles that display phenomenology observed in many biological systems. Here we investigate motility-driven annealing and fluidization in these systems and establish a correspondence between the yielding behaviour of glassy systems under active dynamics and their yielding under oscillatory shear. The yielded region of the phase diagram correlates with tissue fluidization, whereas the annealing region explains age-related maturation and stiffening. This suggests that some mechanical changes observed in ageing tissues can partially stem from processes analogous to enhanced ageing observed in active glasses. In addition to showing similar yielding diagrams, we strengthen the correspondence to oscillatory shear by demonstrating diverging time scales to steady states, the possibility of memory encoding and reading, and the importance of stress reversals in the annealing process in both cases. Finally, we study yielding in active solids and demonstrate that given the correct geometry, one can either suppress or promote brittle failure via shear band formation by tuning activity. Active glasses are dense, disordered structures made up of motile constituents. Simulations now show that motility-driven annealing in such systems leads to mechanical changes, including increased brittleness.","PeriodicalId":19100,"journal":{"name":"Nature Physics","volume":"21 2","pages":"253-261"},"PeriodicalIF":17.6,"publicationDate":"2025-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41567-024-02724-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142917053","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}

{"title":"Observation of microscopic confinement dynamics by a tunable topological θ-angle","authors":"Wei-Yong Zhang, Ying Liu, Yanting Cheng, Ming-Gen He, Han-Yi Wang, Tian-Yi Wang, Zi-Hang Zhu, Guo-Xian Su, Zhao-Yu Zhou, Yong-Guang Zheng, Hui Sun, Bing Yang, Philipp Hauke, Wei Zheng, Jad C. Halimeh, Zhen-Sheng Yuan, Jian-Wei Pan","doi":"10.1038/s41567-024-02702-x","DOIUrl":"10.1038/s41567-024-02702-x","url":null,"abstract":"The topological θ-angle is central to several gauge theories in condensed-matter and high-energy physics. For example, it is responsible for the strong CP problem in quantum chromodynamics and can emerge in effective theories of electrodynamics in topological insulators. Although analogue quantum simulators potentially offer a venue for realizing and controlling the θ-angle, doing so has hitherto remained an outstanding challenge. Here, we describe the experimental realization of a tunable topological θ-angle in a Bose–Hubbard gauge-theory quantum simulator, which was implemented through a tilted superlattice potential that induces an effective background electric field. We demonstrate the emerging physics through the direct observation of the confinement–deconfinement transition of (1 + 1)-dimensional quantum electrodynamics. Using an atomic-precision quantum gas microscope, we distinguish between the confined and deconfined phases by monitoring the real-time evolution of particle–antiparticle pairs. Our work provides a step forward in the realization of topological terms on modern quantum simulators. Topological terms arise naturally in gauge theories but have been difficult to implement in quantum simulators. Now, a tunable topological θ-angle is demonstrated with a cold-atom platform.","PeriodicalId":19100,"journal":{"name":"Nature Physics","volume":"21 1","pages":"155-160"},"PeriodicalIF":17.6,"publicationDate":"2024-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142857544","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}