Reports on progress in physics. Physical Society (Great Britain)最新文献_第6页

Continuous gated first-passage processes. 连续的门控第一通道流程。

Reports on progress in physics. Physical Society (Great Britain) Pub Date : 2024-09-19 DOI: 10.1088/1361-6633/ad7530

Yuval Scher, Aanjaneya Kumar, M S Santhanam, Shlomi Reuveni

{"title":"Continuous gated first-passage processes.","authors":"Yuval Scher, Aanjaneya Kumar, M S Santhanam, Shlomi Reuveni","doi":"10.1088/1361-6633/ad7530","DOIUrl":"10.1088/1361-6633/ad7530","url":null,"abstract":"Gated first-passage processes, where completion depends on both hitting a target and satisfying additional constraints, are prevalent across various fields. Despite their significance, analytical solutions to basic problems remain unknown, e.g. the detection time of a diffusing particle by a gated interval, disk, or sphere. In this paper, we elucidate the challenges posed by continuous gated first-passage processes and present a renewal framework to overcome them. This framework offers a unified approach for a wide range of problems, including those with single-point, half-line, and interval targets. The latter have so far evaded exact solutions. Our analysis reveals that solutions to gated problems can be obtained directly from the ungated dynamics. This, in turn, reveals universal properties and asymptotic behaviors, shedding light on cryptic intermediate-time regimes and refining the notion of high-crypticity for continuous-space gated processes. Moreover, we extend our formalism to higher dimensions, showcasing its versatility and applicability. Overall, this work provides valuable insights into the dynamics of continuous gated first-passage processes and offers analytical tools for studying them across diverse domains.","PeriodicalId":74666,"journal":{"name":"Reports on progress in physics. Physical Society (Great Britain)","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142115766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Determinant- and Derivative-Free Quantum Monte Carlo Within the Stochastic Representation of Wavefunctions. 波函数随机表示法中的无确定性和无衍生量子蒙特卡罗。

Reports on progress in physics. Physical Society (Great Britain) Pub Date : 2024-09-19 DOI: 10.1088/1361-6633/ad7d33

Liam Bernheimer, Hristiana Atanasova, Guy Cohen

{"title":"Determinant- and Derivative-Free Quantum Monte Carlo Within the Stochastic Representation of Wavefunctions.","authors":"Liam Bernheimer, Hristiana Atanasova, Guy Cohen","doi":"10.1088/1361-6633/ad7d33","DOIUrl":"https://doi.org/10.1088/1361-6633/ad7d33","url":null,"abstract":"Describing the ground states of continuous, real-space quantum many-body systems, like atoms and molecules, is a significant computational challenge with applications throughout the physical sciences. Recent progress was made by variational methods based on machine learning (ML) ansatzes. However, since these approaches are based on energy minimization, ansatzes must be twice differentiable. This (a) precludes the use of many powerful classes of ML models; and (b) makes the enforcement of bosonic, fermionic, and other symmetries costly. Furthermore, (c) the optimization procedure is often unstable unless it is done by imaginary time propagation, which is often impractically expensive in modern ML models with many parameters. The stochastic representation of wavefunctions (SRW), introduced in Nat Commun 14, 3601 (2023), is a recent approach to overcoming (c). SRW enables imaginary time propagation at scale, and makes some headway towards the solution of problem (b), but remains limited by problem (a). Here, we argue that combining SRW with path integral techniques leads to a new formulation that overcomes all three problems simultaneously. As a demonstration, we apply the approach to generalized ``Hooke's atoms'': interacting particles in harmonic wells. We benchmark our results against state-of-the-art data where possible, and use it to investigate the crossover between the Fermi liquid and the Wigner molecule within closed-shell systems. Our results shed new light on the competition between interaction-driven symmetry breaking and kinetic-energy-driven delocalization.","PeriodicalId":74666,"journal":{"name":"Reports on progress in physics. Physical Society (Great Britain)","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142302916","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Supersymmetry dictated topology in periodic gauge fields and realization in strained and twisted 2D materials. 超对称性决定了周期性规规场的拓扑结构，并在应变和扭曲的二维材料中得以实现。

Reports on progress in physics. Physical Society (Great Britain) Pub Date : 2024-09-18 DOI: 10.1088/1361-6633/ad77f0

Dawei Zhai, Zuzhang Lin, Wang Yao

{"title":"Supersymmetry dictated topology in periodic gauge fields and realization in strained and twisted 2D materials.","authors":"Dawei Zhai, Zuzhang Lin, Wang Yao","doi":"10.1088/1361-6633/ad77f0","DOIUrl":"10.1088/1361-6633/ad77f0","url":null,"abstract":"Supersymmetry (SUSY) of a Hamiltonian dictates double degeneracy between a pair of superpartners (SPs) transformed by supercharge, except at zero energy where modes remain unpaired in many cases. Here we explore a SUSY of complete isospectrum between SPs-with paired zero modes-realized by 2D electrons in zero-flux periodic gauge fields, which can describe twisted or periodically strained 2D materials. We find their low-energy sector containing zero (or threshold) modes must be topologically non-trivial, by proving that Chern numbers of the two SPs have a finite difference dictated by the number of zero modes and energy dispersion in their vicinity. In 30° twisted bilayer (double bilayer) transition metal dichalcogenides subject to periodic strain, we find one SP is topologically trivial in its lowest miniband, while the twin SP of identical dispersion has a Chern number of 1 (2), in stark contrast to time-reversal partners that have to be simultaneously trivial or nontrivial. For systems whose physical Hamiltonian corresponds to the square root of a SUSY Hamiltonian, such as twisted or strained bilayer graphene, we reveal that topological properties of the two SUSY SPs are transferred respectively to the conduction and valence bands, including the contrasted topology in the low-energy sector and identical topology in the high-energy sector. This offers a unified perspective for understanding topological properties in many flat-band systems described by such square-root models. Both types of SUSY systems provide unique opportunities for exploring correlated and topological phases of matter.","PeriodicalId":74666,"journal":{"name":"Reports on progress in physics. Physical Society (Great Britain)","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142147054","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

From fractional quantum anomalous Hall smectics to polar smectic metals: nontrivial interplay between electronic liquid crystal order and topological order in correlated topological flat bands. 从分数量子反常霍尔 Smectics 到极性 Smectic Metals：电子液晶秩序与相关拓扑平坦带中拓扑秩序之间的非微观相互作用。

Reports on progress in physics. Physical Society (Great Britain) Pub Date : 2024-09-11 DOI: 10.1088/1361-6633/ad7640

Hongyu Lu, Han-Qing Wu, Bin-Bin Chen, Kai Sun, Zi Yang Meng

{"title":"From fractional quantum anomalous Hall smectics to polar smectic metals: nontrivial interplay between electronic liquid crystal order and topological order in correlated topological flat bands.","authors":"Hongyu Lu, Han-Qing Wu, Bin-Bin Chen, Kai Sun, Zi Yang Meng","doi":"10.1088/1361-6633/ad7640","DOIUrl":"10.1088/1361-6633/ad7640","url":null,"abstract":"Symmetry-breaking orders can not only compete with each other, but also be intertwined, and the intertwined topological and symmetry-breaking orders make the situation more intriguing. This work examines the archetypal correlated flat band model on a checkerboard lattice at fillingν=2/3and we find that the unique interplay between smectic charge order and topological order gives rise to two novel quantum states. As the interaction strength increases, the system first transitions from a Fermi liquid (FL) into FQAH smectic (FQAHS) state, where the topological order coexists cooperatively with smectic charge order with enlarged ground-state degeneracy and interestingly, the Hall conductivity isσxy=ν=2/3, different from the band-folding or doping scenarios. Further increasing the interaction strength, the system undergoes another quantum phase transition and evolves into a polar smectic metal (PSM) state. This emergent PSM is an anisotropic non-Fermi liquid, whose interstripe tunneling is irrelevant while it is metallic inside each stripe. Different from the FQAHS and conventional smectic orders, this PSM spontaneously breaks the two-fold rotational symmetry, resulting in a nonzero electric dipole moment and ferroelectric order. In addition to the exotic ground states, large-scale numerical simulations are also used to study low-energy excitations and thermodynamic characteristics. We find that the onset temperature of the incompressible FQAHS state, which also coincides with the onset of non-polar smectic order, is dictated by the magneto-roton modes. Above this onset temperature, the PSM state exists at an intermediate-temperature regime. Although theT = 0 quantum phase transition between PSM and FQAHS is first order, the thermal FQAHS-PSM transition could be continuous. We expect the features of the exotic states and thermal phase transitions could be accessed in future experiments.","PeriodicalId":74666,"journal":{"name":"Reports on progress in physics. Physical Society (Great Britain)","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142121296","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Reports on progress in physics. Physical Society (Great Britain) Pub Date : 2024-09-09 DOI: 10.1088/1361-6633/ad7058

Chao Xu, Yixin Ma, Shenghan Jiang

{"title":"Unveiling correlated two-dimensional topological insulators through fermionic tensor network states-classification, edge theories and variational wavefunctions.","authors":"Chao Xu, Yixin Ma, Shenghan Jiang","doi":"10.1088/1361-6633/ad7058","DOIUrl":"10.1088/1361-6633/ad7058","url":null,"abstract":"The study of topological band insulators has revealed fascinating phases characterized by band topology indices and anomalous boundary modes protected by global symmetries. In strongly correlated systems, where the traditional notion of electronic bands becomes obsolete, it has been established that topological insulator phases persist as stable phases, separate from the trivial insulators. However, due to the inability to express the ground states of such systems as Slater determinants, the formulation of generic variational wave functions for numerical simulations is highly desirable. In this paper, we tackle this challenge for two-dimensional topological insulators by developing a comprehensive framework for fermionic tensor network states. Starting from simple assumptions, we obtain possible sets of tensor equations for any given symmetry group, capturing consistent relations governing symmetry transformation rules on tensor legs. We then examine the connection between these tensor equations andnon-chiraltopological insulators by constructing edge theories and extracting quantum anomaly data from each set of tensor equations. By exhaustively exploring all possible sets of equations, we achieve a systematic classification of non-chiral topological insulator phases. Imposing the solutions of a given set of equations onto local tensors, we obtain generic variational wavefunctions for the corresponding topological insulator phases. Our methodology provides an important step toward simulating topological insulators in strongly correlated systems. We discuss the limitations and potential generalizations of our results, paving the way for further advancements in this field.","PeriodicalId":74666,"journal":{"name":"Reports on progress in physics. Physical Society (Great Britain)","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141997051","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Emergent symmetry in TbTe₃revealed by ultrafast reflectivity under anisotropic strain. 各向异性应变下的超快反射率揭示了碲化镉中的新兴对称性。

Reports on progress in physics. Physical Society (Great Britain) Pub Date : 2024-09-02 DOI: 10.1088/1361-6633/ad71ee

Soyeun Kim, Gal Orenstein, Anisha G Singh, Ian R Fisher, David A Reis, Mariano Trigo

引用次数: 0

Observation ofγγ→ττin proton-proton collisions and limits on the anomalous electromagnetic moments of the τ lepton. 质子-质子碰撞中γγ→ττ的观测以及对τ轻子反常电磁矩的限制。

Reports on progress in physics. Physical Society (Great Britain) Pub Date : 2024-09-02 DOI: 10.1088/1361-6633/ad6fcb

The Cms Collaboration

引用次数: 0

Topological Anderson phases in heat transport. 热传输中的拓扑安德森相。

Reports on progress in physics. Physical Society (Great Britain) Pub Date : 2024-08-23 DOI: 10.1088/1361-6633/ad6d88

He Gao, Guoqiang Xu, Xue Zhou, Shuihua Yang, Zhongqing Su, Cheng-Wei Qiu

引用次数: 0

Generally applicable physics-based equation of state for liquids. 普遍适用的基于物理学的液体状态方程。

Reports on progress in physics. Physical Society (Great Britain) Pub Date : 2024-08-22 DOI: 10.1088/1361-6633/ad6a80

J E Proctor, Kostya Trachenko

{"title":"Generally applicable physics-based equation of state for liquids.","authors":"J E Proctor, Kostya Trachenko","doi":"10.1088/1361-6633/ad6a80","DOIUrl":"10.1088/1361-6633/ad6a80","url":null,"abstract":"Physics-based first-principles pressure-volume-temperature equations of state (EOS) exist for solids and gases but not for liquids due to the long-standing fundamental problems involved in liquid theory. Current EOS models that are applicable to liquids and supercritical fluids at liquid-like density under conditions relevant to planetary interiors and industrial processes are complex empirical models with many physically meaningless adjustable parameters. Here, we develop a generally applicable physics-based (GAP) EOS for liquids including supercritical fluids at liquid-like density. The GAP equation is explicit in the internal energy, and hence links the most fundamental macroscopic static property of fluids, the pressure-volume-temperature EOS, to their key microscopic property: the molecular hopping frequency or liquid relaxation time, from which the internal energy can be obtained. We test our GAP equation against available experimental data in several different ways and find good agreement. Our GAP equation, unavoidably and similarly to solid EOS, contains a semi-empirical term giving the energy of the static sample as a function of volume only (EST(V)). Our testing includes studies along isochores, in order to examine the validity of the GAP equation independently of the validity of any function we may choose to utilize forEST(V). The only other adjustable parameter in the equation is the Grüneisen parameter for the fluid. We observe that the GAP equation is similar to the Mie-Grüneisen solid EOS in a wide range of the liquid phase diagram. This similarity is ultimately related to the condensed state of these two phases. On the other hand, the differences between the GAP equation and EOS for gases are fundamental. Finally, we identify the key gaps in the experimental data that need to be filled in to proceed further with the liquid EOS.","PeriodicalId":74666,"journal":{"name":"Reports on progress in physics. Physical Society (Great Britain)","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141879892","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Dynamically generated decoherence-free subspaces and subsystems on superconducting qubits. 超导量子比特上动态生成的无退相干子空间和子系统。

Reports on progress in physics. Physical Society (Great Britain) Pub Date : 2024-08-14 DOI: 10.1088/1361-6633/ad6805

Gregory Quiroz, Bibek Pokharel, Joseph Boen, Lina Tewala, Vinay Tripathi, Devon Williams, Lian-Ao Wu, Paraj Titum, Kevin Schultz, Daniel Lidar

{"title":"Dynamically generated decoherence-free subspaces and subsystems on superconducting qubits.","authors":"Gregory Quiroz, Bibek Pokharel, Joseph Boen, Lina Tewala, Vinay Tripathi, Devon Williams, Lian-Ao Wu, Paraj Titum, Kevin Schultz, Daniel Lidar","doi":"10.1088/1361-6633/ad6805","DOIUrl":"10.1088/1361-6633/ad6805","url":null,"abstract":"Decoherence-free subspaces and subsystems (DFS) preserve quantum information by encoding it into symmetry-protected states unaffected by decoherence. An inherent DFS of a given experimental system may not exist; however, through the use of dynamical decoupling (DD), one can induce symmetries that support DFSs. Here, we provide the first experimental demonstration of DD-generated decoherence-free subsystem logical qubits. Utilizing IBM Quantum superconducting processors, we investigate two and three-qubit DFS codes comprising up to six and seven noninteracting logical qubits, respectively. Through a combination of DD and error detection, we show that DFS logical qubits can achieve up to a 23% improvement in state preservation fidelity over physical qubits subject to DD alone. This constitutes a beyond-breakeven fidelity improvement for DFS-encoded qubits. Our results showcase the potential utility of DFS codes as a pathway toward enhanced computational accuracy via logical encoding on quantum processors.","PeriodicalId":74666,"journal":{"name":"Reports on progress in physics. Physical Society (Great Britain)","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141768218","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0