Reports on Progress in Physics最新文献

{"title":"Measurement of off-shell Higgs boson production in the H ∗ →...","authors":"The ATLAS Collaboration","doi":"10.1088/1361-6633/adcd9a","DOIUrl":"https://doi.org/10.1088/1361-6633/adcd9a","url":null,"abstract":"A measurement of off-shell Higgs boson production in the decay channel is presented. The measurement uses 140 fb−1 of proton–proton collisions at TeV collected by the ATLAS detector at the Large Hadron Collider and supersedes the previous result in this decay channel using the same dataset. The data analysis is performed using a neural simulation-based inference method, which builds per-event likelihood ratios using neural networks. The observed (expected) off-shell Higgs boson production signal strength in the decay channel at 68% CL is ( ). The evidence for off-shell Higgs boson production using the decay channel has an observed (expected) significance of 2.5σ (1.3σ). The expected result represents a significant improvement relative to that of the previous analysis of the same dataset, which obtained an expected significance of 0.5σ. When combined with the most recent ATLAS measurement in the decay channel, the evidence for off-shell Higgs boson production has an observed (expected) significance of 3.7σ (2.4σ). The off-shell measurements are combined with the measurement of on-shell Higgs boson production to obtain constraints on the Higgs boson total width. The observed (expected) value of the Higgs boson width at 68% CL is ( ) MeV.","PeriodicalId":21110,"journal":{"name":"Reports on Progress in Physics","volume":"78 1","pages":""},"PeriodicalIF":18.1,"publicationDate":"2025-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143979527","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":"Active phase separation: new phenomenology from non-equilibrium physics","authors":"M E Cates and C Nardini","doi":"10.1088/1361-6633/add278","DOIUrl":"https://doi.org/10.1088/1361-6633/add278","url":null,"abstract":"In active systems, whose constituents have non-equilibrium dynamics at local level, fluid-fluid phase separation is widely observed. Examples include the formation of membraneless organelles within cells; the clustering of self-propelled colloidal particles in the absence of attractive forces, and some types of ecological segregation. A schematic understanding of such active phase separation was initially borrowed from what is known for the equilibrium case, in which detailed balance holds at microscopic level. However it has recently become clear that in active systems the absence of detailed balance, although it leave phase separation qualitatively unchanged in some regimes (for example domain growth driven by interfacial tension via Ostwald ripening), can in other regimes radically alter its phenomenology at mechanistic level. For example, microphase separation can be caused by reverse Ostwald ripening, a process that is hard to imagine from an equilibrium perspective. This and other new phenomena arise because, instead of having a single, positive interfacial tension like their equilibrium counterparts, the fluid-fluid interfaces created by active phase separation can have several distinct interfacial tensions governing different properties, some of which can be negative. These phenomena can be broadly understood by studying continuum field theories for a single conserved scalar order parameter (the fluid density), supplemented with a velocity field in cases where momentum conservation is also present. More complex regimes arise in systems described by multiple scalar order parameters (especially with nonreciprocal interactions between these); or when an order parameter undergoes both conserved and non-conserved dynamics (such that the combination breaks detailed balance); or in systems that support orientational long-range order in one or more of the coexisting phases. In this Review, we survey recent progress in understanding the specific role of activity in phase separation, drawing attention to many open questions. We focus primarily on continuum theories, especially those with a single scalar order parameter, reviewing both analytical and numerical work. We compare their predictions with particle-based models, which have mostly been studied numerically although a few have been explicitly coarse-grained to continuum level. We also compare, where possible, with experimental results. In the latter case, qualitative comparisons are broadly encouraging whereas quantitative ones are hindered by the dynamical complexity of most experimental systems relative that of simplified (particle-level or continuum) models of active matter.","PeriodicalId":21110,"journal":{"name":"Reports on Progress in Physics","volume":"10 1","pages":""},"PeriodicalIF":18.1,"publicationDate":"2025-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143945968","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":"Magnon damping and mode softening in quantum double-exchange ferromagnets.","authors":"Adriana Moreo,Elbio Dagotto,Gonzalo Alvarez,Takami Tohyama,Marcin P Mierzejewski,Jacek Herbrych","doi":"10.1088/1361-6633/add6d4","DOIUrl":"https://doi.org/10.1088/1361-6633/add6d4","url":null,"abstract":"We present a comprehensive analysis of the magnetic excitations and electronic properties of {it fully quantum} double-exchange ferromagnets, i.e., systems where ferromagnetic ordering emerges from the competition between spin, charge, and orbital degrees of freedom, but without the canonical approximation of using classical localized spins. Specifically, we investigate spin excitations within the Kondo lattice-like model, as well as a two-orbital Hubbard Hamiltonian in proximity to the orbital-selective Mott phase. Computational analysis of the magnon dispersion, damping, and spectral weight within these models reveals unexpected phenomena, such as magnon mode softening and the anomalous decoherence of magnetic excitations as observed in earlier experimental efforts, but explained here without the use of the phononic degrees of freedom. We show that these effects are intrinsically linked to incoherent spectral features near the Fermi level, which arise due to the quantum nature of the local (on-site) triplets. This incoherent spectrum leads to a Stoner-like continuum on which spin excitations scatter, governing magnon lifetime and strongly influencing the dynamical spin structure factor. Our study explores the transition from coherent to incoherent magnon spectra by varying the electron density. Furthermore, we demonstrate that the magnitude of the localized spin mitigates decoherence by suppressing the incoherent spectral contributions near the Fermi level. We also discuss the effective $J_1$-$J_2$ spin Hamiltonian, which can accurately describe the large doping region characterized by the magnon-mode softening. Finally, we show that this behavior is also present in multiorbital models with partially filled orbitals, namely, in systems without localized spin moments, provided that the model is in a strong coupling regime. Our results potentially have far-reaching implications for understanding ferromagnetic ordering in various multi-band systems. These findings establish a previously unknown direct connection between the electronic correlations of those materials and spin excitations.","PeriodicalId":21110,"journal":{"name":"Reports on Progress in Physics","volume":"140 1","pages":""},"PeriodicalIF":18.1,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143932516","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":"Landauer principle and thermodynamics of computation.","authors":"Pritam Chattopadhyay,Avijit Misra,Tanmoy Pandit,Goutam Paul","doi":"10.1088/1361-6633/add6b3","DOIUrl":"https://doi.org/10.1088/1361-6633/add6b3","url":null,"abstract":"According to the Landauer principle, any logically irreversible process accompanies entropy production which results in heat dissipation in the environment. Erasing of information, one of the primary logically irreversible processes has a lower bound on heat dissipated into the environment, called the Landuaer bound (LB). However, the practical erasure processes dissipate much more heat than the LB. Recently there have been a few experimental investigations to reach this bound both in the classical and quantum domains. There has also been a spate of activities to enquire about this LB in finite time, with finite size heat baths, non-Markovian and nonequilibrium environment in the quantum regime where the effects of fluctuations and correlation of the systems with the bath can no longer be ignored. This article provides a comprehensive review of the recent progress on the Landauer bound, which serves as a fundamental principle in the thermodynamics of computation. We also provide a perspective for future endeavors in these directions.

Furthermore, we review the recent exploration toward establishing energetic bounds of a computational process. We also review the thermodynamic aspects of error correction which is an indispensable part of information processing and computations. In doing so, we briefly discuss the basics of these fields to provide a complete picture.&#xD.","PeriodicalId":21110,"journal":{"name":"Reports on Progress in Physics","volume":"1 1","pages":""},"PeriodicalIF":18.1,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143932517","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":"Corrigendum: Fundamental concepts, design rules and potentials in radiative cooling (2025Rep. Prog. Phys.88 045901).","authors":"Zhuning Wang,Sijie Pian,Yulei Zhang,Yaoguang Ma","doi":"10.1088/1361-6633/add1ed","DOIUrl":"https://doi.org/10.1088/1361-6633/add1ed","url":null,"abstract":"","PeriodicalId":21110,"journal":{"name":"Reports on Progress in Physics","volume":"20 1","pages":""},"PeriodicalIF":18.1,"publicationDate":"2025-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143920980","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":"How to seed ergodic dynamics of interacting bosons under conditions of many-body quantum chaos","authors":"Lukas Pausch, Edoardo G Carnio, Andreas Buchleitner and Alberto Rodríguez","doi":"10.1088/1361-6633/add0de","DOIUrl":"https://doi.org/10.1088/1361-6633/add0de","url":null,"abstract":"We demonstrate how the initial state of ultracold atoms in an optical lattice controls the emergence of ergodic dynamics as the underlying spectral structure is tuned into the quantum chaotic regime. Distinct initial states’ chaos threshold values in terms of tunneling as compared to interaction strength are identified, as well as dynamical signatures of the chaos transition, on the level of experimentally accessible observables and time scales.","PeriodicalId":21110,"journal":{"name":"Reports on Progress in Physics","volume":"96 1","pages":"057602"},"PeriodicalIF":18.1,"publicationDate":"2025-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143920384","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":"Certification of genuinely entangled subspaces of the five qubit code via robust self-testing.","authors":"Yu Guo,Hao Tang,Jiaxuan Zhang,Jiale Miao,Xiao-Min Hu,Wu Yu-Chun,GuoPing Guo,Yun-Feng Huang,Chuan-Feng Li,Guang-Can Guo,Bi-Heng Liu","doi":"10.1088/1361-6633/add560","DOIUrl":"https://doi.org/10.1088/1361-6633/add560","url":null,"abstract":"Self-testing provides a device-independent framework for certifying quantum properties based solely on input-output statistics while treating quantum devices as black boxes. It has evolved significantly from its origins in bipartite systems to applications in multipartite entanglement and, more recently, genuinely entangled subspaces. Notably, It has been revealed that the logical subspaces of numerous stabilizer quantum error correction codes are exclusively composed of genuinely multipartite entangled states, opening new avenues for developing device-independent tools to characterize these subspaces. In this work, we leverage the self-testing technique to certify genuinely entangled logical subspaces within the five-qubit code using both photonic and superconducting platforms. This is achieved by preparing informationally complete logical states, simulating Pauli errors on a physical qubit, and testing several stabilizer-formalized Bell inequalities. Our certification is supported by an extractability measure of at least $0.828pm0.006$ and $0.621pm0.007$ for the photonic and superconducting systems, respectively. Our results demonstrate the feasibility of device-independent certification of general entangled quantum structures in experimental settings, extending beyond quantum states and quantum measurements.","PeriodicalId":21110,"journal":{"name":"Reports on Progress in Physics","volume":"48 1","pages":""},"PeriodicalIF":18.1,"publicationDate":"2025-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143920977","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":"Metal-insulator transitions in pyrochlore oxides","authors":"Yoshinori Tokura, Yukitoshi Motome and Kentaro Ueda","doi":"10.1088/1361-6633/add0c5","DOIUrl":"https://doi.org/10.1088/1361-6633/add0c5","url":null,"abstract":"Pyrochlore oxides with chemical formula of O7 exhibit a diverse range of electronic properties as a representative family of quantum materials. These properties mostly stem from strong electron correlations at the transition metal B site and typical geometrical frustration effects on the pyrochlore lattice. Furthermore, the coupling between the magnetic moments of the rare-earth A site and the conduction electrons at the B site, along with the relativistic spin–orbit coupling particularly affecting the 4d/5d electrons at the B site, gives rise to the topological characteristics of the correlated electrons. This review paper focuses on the metal–insulator transitions in pyrochlore oxides as evidence of the strong electron correlation, which is highlighted as a rich source of intriguing charge dynamics coupled with frustrated spin-orbital entangled magnetism.","PeriodicalId":21110,"journal":{"name":"Reports on Progress in Physics","volume":"26 1","pages":""},"PeriodicalIF":18.1,"publicationDate":"2025-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143915431","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":"Gravity generated by four one-dimensional unitary gauge symmetries and the Standard Model","authors":"Mikko Partanen, Jukka Tulkki","doi":"10.1088/1361-6633/adc82e","DOIUrl":"https://doi.org/10.1088/1361-6633/adc82e","url":null,"abstract":"The Standard Model of particle physics describes electromagnetic, weak, and strong interactions, which are three of the four known fundamental forces of nature. The unification of the fourth interaction, gravity, with the Standard Model has been challenging due to incompatibilities of the underlying theories—general relativity and quantum field theory. While quantum field theory utilizes compact, finite-dimensional symmetries associated with the internal degrees of freedom of quantum fields, general relativity is based on noncompact, infinite-dimensional external space-time symmetries. The present work aims at deriving the gauge theory of gravity using compact, finite-dimensional symmetries in a way that resembles the formulation of the fundamental interactions of the Standard Model. For our eight-spinor representation of the Lagrangian, we define a quantity, called the space-time dimension field, which enables extracting four-dimensional space-time quantities from the eight-dimensional spinors. Four U(1) symmetries of the components of the space-time dimension field are used to derive a gauge theory, called unified gravity. The stress-energy-momentum tensor source term of gravity follows directly from these symmetries. The metric tensor enters in unified gravity through geometric conditions. We show how the teleparallel equivalent of general relativity in the Weitzenböck gauge is obtained from unified gravity by a gravity-gauge-field-dependent geometric condition. Unified gravity also enables a gravity-gauge-field-independent geometric condition that leads to an exact description of gravity in the Minkowski metric. This differs from the use of metric in general relativity, where the metric depends on the gravitational field by definition. Based on the Minkowski metric, unified gravity allows us to describe gravity within a single coherent mathematical framework together with the quantum fields of all fundamental interactions of the Standard Model. We present the Feynman rules for unified gravity and study the renormalizability and radiative corrections of the theory at one-loop order. The equivalence principle is formulated by requiring that the renormalized values of the inertial and gravitational masses are equal. In contrast to previous gauge theories of gravity, all infinities that are encountered in the calculations of loop diagrams can be absorbed by the redefinition of the small number of parameters of the theory in the same way as in the gauge theories of the Standard Model. This result and our observation that unified gravity fulfills the Becchi–Rouet–Stora–Tyutin (BRST) symmetry and its coupling constant is dimensionless suggest that unified gravity can provide the basis for a complete, renormalizable theory of quantum gravity.","PeriodicalId":21110,"journal":{"name":"Reports on Progress in Physics","volume":"8 1","pages":""},"PeriodicalIF":18.1,"publicationDate":"2025-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143898279","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":"Giant In-plane Anisotropy in Novel Quasi-one-dimensional Van der Waals crystal.","authors":"Hong Zhou,Jiao Qi,Shaojun Fang,Jiajun Ma,Hongyu Tang,Chuanxiang Sheng,Yu-Xiang Zheng,Hao Zhang,Weibo Duan,Shaojuan Li,Rong-Jun Zhang","doi":"10.1088/1361-6633/add209","DOIUrl":"https://doi.org/10.1088/1361-6633/add209","url":null,"abstract":"Large optical anisotropy is paramount for advancing light manipulation in modern optic. Therefore, there has been an intensive search for materials exhibiting giant optical anisotropy. However, the reported in-plane birefringence of most materials remains relatively low, posing substantial limitations for applications in integrated optics and polarization-sensitive technologies. Here we present a systematic investigation of the in-plane anisotropic properties of the quasi -one-dimensional van der Waals crystal-Ta2NiSe5, employing spectroscopic ellipsometry, angle-resolved polarization Raman spectroscopy, azimuth-dependent reflectance difference microscopy and angle-dependent electronic and optoelectronic techniques. Notably, our study reveals a record-breaking giant in-plane birefringence of up to 2.0 across the visible to infrared spectral region, representing the highest value reported among van der Waals materials to date. Meanwhile, the physical origin of this extraordinary optical anisotropy is elucidated through first-principles calculations, attributing it to the synergistic effects of significant polarizability contrast and the quasi-one-dimensional crystal arrangement. Furthermore, photodetectors based on Ta2NiSe5flakes exhibit remarkable performance, including a broad photoresponse spanning 520-2000 nm, ultrafast response time of 75 μs, a pronounced dichroic ratio of up to 1.89 and high-resolution polarized light imaging capabilities. Our work not only highlights the immense potential of Ta2NiSe5for next-generation polarization-sensitive optoelectronic devices but also inspire innovative approaches for next-generation ultracompact integrated photonics based on quasi-one-dimensional van der Waals materials.","PeriodicalId":21110,"journal":{"name":"Reports on Progress in Physics","volume":"91 1","pages":""},"PeriodicalIF":18.1,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143893170","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}