SciPost Physics最新文献_第4页

Quantum-critical properties of the one- and two-dimensional random transverse-field Ising model from large-scale quantum Monte Carlo simulations 从大规模量子蒙特卡罗模拟看一维和二维随机横向场伊辛模型的量子临界特性

IF 5.5 2区物理与天体物理

SciPost Physics Pub Date : 2024-08-23 DOI: 10.21468/scipostphys.17.2.061

Calvin Krämer, Jan Alexander Koziol, Anja Langheld, Max Hörmann, Kai Phillip Schmidt

{"title":"Quantum-critical properties of the one- and two-dimensional random transverse-field Ising model from large-scale quantum Monte Carlo simulations","authors":"Calvin Krämer, Jan Alexander Koziol, Anja Langheld, Max Hörmann, Kai Phillip Schmidt","doi":"10.21468/scipostphys.17.2.061","DOIUrl":"https://doi.org/10.21468/scipostphys.17.2.061","url":null,"abstract":"We study the ferromagnetic transverse-field Ising model with quenched disorder at $T = 0$ in one and two dimensions by means of stochastic series expansion quantum Monte Carlo simulations using a rigorous zero-temperature scheme. Using a sample-replication method and averaged Binder ratios, we determine the critical shift and width exponents $nu_mathrm{s}$ and $nu_mathrm{w}$ as well as unbiased critical points by finite-size scaling. Further, scaling of the disorder-averaged magnetisation at the critical point is used to determine the order-parameter critical exponent $beta$ and the critical exponent $nu_{mathrm{av}}$ of the average correlation length. The dynamic scaling in the Griffiths phase is investigated by measuring the local susceptibility in the disordered phase and the dynamic exponent $z'$ is extracted. By applying various finite-size scaling protocols, we provide an extensive and comprehensive comparison between the different approaches on equal footing. The emphasis on effective zero-temperature simulations resolves several inconsistencies in existing literature.","PeriodicalId":21682,"journal":{"name":"SciPost Physics","volume":"33 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2024-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142187447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}

引用次数: 0

Mode-shell correspondence, a unifying phase space theory in topological physics - Part I: Chiral number of zero-modes 模壳对应，拓扑物理学中的统一相空间理论--第一部分：零模的手性数

IF 5.5 2区物理与天体物理

SciPost Physics Pub Date : 2024-08-23 DOI: 10.21468/scipostphys.17.2.060

Lucien Jezequel, Pierre Delplace

引用次数: 0

A non-unitary bulk-boundary correspondence: Non-unitary Haagerup RCFTs from S-fold SCFTs 非单元体-边界对应：来自 S-fold SCFT 的非统一哈格鲁普 RCFT

IF 5.5 2区物理与天体物理

SciPost Physics Pub Date : 2024-08-23 DOI: 10.21468/scipostphys.17.2.064

Dongmin Gang, Dongyeob Kim, Sungjay Lee

引用次数: 0

One-dimensional Fermi polaron after a kick: Two-sided singularity of the momentum distribution, Bragg reflection and other exact results 脚踢后的一维费米极子：动量分布的双面奇异性、布拉格反射和其他精确结果

IF 5.5 2区物理与天体物理

SciPost Physics Pub Date : 2024-08-23 DOI: 10.21468/scipostphys.17.2.063

Oleksandr Gamayun, Oleg Lychkovskiy

{"title":"One-dimensional Fermi polaron after a kick: Two-sided singularity of the momentum distribution, Bragg reflection and other exact results","authors":"Oleksandr Gamayun, Oleg Lychkovskiy","doi":"10.21468/scipostphys.17.2.063","DOIUrl":"https://doi.org/10.21468/scipostphys.17.2.063","url":null,"abstract":"A mobile impurity particle immersed in a quantum fluid forms a polaron - a quasiparticle consisting of the impurity and a local disturbance of the fluid around it. We ask what happens to a one-dimensional polaron after a kick, i.e. an abrupt application of a force that instantly delivers a finite impulse to the impurity. In the framework of an integrable model describing an impurity in a one-dimensional gas of fermions or hard-core bosons, we calculate the distribution of the polaron momentum established when the post-kick relaxation is over. A remarkable feature of this distribution is a two-sided power-law singularity. It emerges due to one of two processes. In the first process, the whole impulse is transferred to the polaron, without creating phonon-like excitations of the fluid. In the second process, the impulse is shared between the polaron and the center-of-mass motion of the fluid, again without creating any fluid excitations. The latter process is, in fact, a Bragg reflection at the edge of the emergent Brillouin zone. We carefully analyze the conditions for each of the two processes. The asymptotic form of the distribution in the vicinity of the singularity is derived.","PeriodicalId":21682,"journal":{"name":"SciPost Physics","volume":"51 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2024-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142187443","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}

引用次数: 0

Density-matrix mean-field theory 密度矩阵平均场理论

IF 5.5 2区物理与天体物理

SciPost Physics Pub Date : 2024-08-23 DOI: 10.21468/scipostphys.17.2.062

Junyi Zhang, Zhengqian Cheng

{"title":"Density-matrix mean-field theory","authors":"Junyi Zhang, Zhengqian Cheng","doi":"10.21468/scipostphys.17.2.062","DOIUrl":"https://doi.org/10.21468/scipostphys.17.2.062","url":null,"abstract":"Mean-field theories have proven to be efficient tools for exploring diverse phases of matter, complementing alternative methods that are more precise but also more computationally demanding. Conventional mean-field theories often fall short in capturing quantum fluctuations, which restricts their applicability to systems with significant quantum effects. In this article, we propose an improved mean-field theory, density-matrix mean-field theory (DMMFT). DMMFT constructs effective Hamiltonians, incorporating quantum environments shaped by entanglements, quantified by the reduced density matrices. Therefore, it offers a systematic and unbiased approach to account for the effects of fluctuations and entanglements in quantum ordered phases. As demonstrative examples, we show that DMMFT can not only quantitatively evaluate the renormalization of order parameters induced by quantum fluctuations, but can also detect the topological quantum phases. Additionally, we discuss the extensions of DMMFT for systems at finite temperatures and those with disorders. Our work provides an efficient approach to explore phases exhibiting unconventional quantum orders, which can be particularly beneficial for investigating frustrated spin systems in high spatial dimensions.","PeriodicalId":21682,"journal":{"name":"SciPost Physics","volume":"13 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2024-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142187442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}

引用次数: 0

x-y duality in topological recursion for exponential variables via quantum dilogarithm 通过量子稀算术实现指数变量拓扑递归中的 x-y 对偶性

IF 5.5 2区物理与天体物理

SciPost Physics Pub Date : 2024-08-23 DOI: 10.21468/scipostphys.17.2.065

Alexander Hock

{"title":"x-y duality in topological recursion for exponential variables via quantum dilogarithm","authors":"Alexander Hock","doi":"10.21468/scipostphys.17.2.065","DOIUrl":"https://doi.org/10.21468/scipostphys.17.2.065","url":null,"abstract":"For a given spectral curve, the theory of topological recursion generates two different families $omega_{g,n}$ and $omega_{g,n}^vee$ of multi-differentials, which are for algebraic spectral curves related via the universal $x-y$ duality formula. We propose a formalism to extend the validity of the $x-y$ duality formula of topological recursion from algebraic curves to spectral curves with exponential variables of the form $e^x=F(e^y)$ or $e^x=F(y)e^{a y}$ with $F$ rational and $a$ some complex number, which was in principle already observed in [Commun. Number Theory Phys. 13, 763 (2019); J. Lond. Math. Soc. 109, e12946 (2024)]. From topological recursion perspective the family $omega_{g,n}^vee$ would be trivial for these curves. However, we propose changing the $n=1$ sector of $omega_{g,n}^vee$ via a version of the Faddeev's quantum dilogarithm which will lead to the correct two families $omega_{g,n}$ and $omega_{g,n}^vee$ related by the same $x-y$ duality formula as for algebraic curves. As a consequence, the $x-y$ symplectic transformation formula extends further to important examples governed by topological recursion including, for instance, Gromov-Witten invariants of $mathbb{C}^3$ (or, equivalently, triple Hodge integrals), orbifold Hurwitz numbers, and stationary Gromov-Witten invariants of $mathbb{P}^1$. The proposed formalism is related to the issue topological recursion encounters for specific choices of framings for the topological vertex curve.","PeriodicalId":21682,"journal":{"name":"SciPost Physics","volume":"1 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2024-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142187452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}

引用次数: 0

Universality and the thermoelectric transport properties of a double quantum dot system: Seeking for conditions that improve the thermoelectric efficiency 双量子点系统的普遍性和热电传输特性：寻找提高热电效率的条件

IF 5.5 2区物理与天体物理

SciPost Physics Pub Date : 2024-08-23 DOI: 10.21468/scipostphyscore.7.3.058

Ronald Santiago Cortes-Santamaria, J. A. Landazabal-Rodríguez, Jereson Silva-Valencia, Edwin Ramos, M. S. Figueira, Roberto Franco Peñaloza

{"title":"Universality and the thermoelectric transport properties of a double quantum dot system: Seeking for conditions that improve the thermoelectric efficiency","authors":"Ronald Santiago Cortes-Santamaria, J. A. Landazabal-Rodríguez, Jereson Silva-Valencia, Edwin Ramos, M. S. Figueira, Roberto Franco Peñaloza","doi":"10.21468/scipostphyscore.7.3.058","DOIUrl":"https://doi.org/10.21468/scipostphyscore.7.3.058","url":null,"abstract":"Employing universal relations for the Onsager coefficients in the linear regime at the symmetric point of the single impurity Anderson model, we calculate the conditions under which the quantum scattering phase shift should satisfy to produce the asymptotic Carnot’s limit for the thermoelectric efficiency. We show that a single quantum dot connected by metallic leads at the Kondo regime cannot achieve the best thermoelectric efficiency. We study a serial double quantum dot system, with the quantum dots immersed in ballistic conduction channels. Each QD exhibits a strong but finite local electronic correlation U. We show that maintaining one dot in the electron-hole symmetric point and allowing charge fluctuations in the other QD makes it possible to drive the system to the maximum thermoelectric efficiency. We also show that the bound states in the continuum (BICs) and quasi-BICs associated with the quantum scattering interference process drive the DQD to the maximum thermoelectric efficiency. We identify two types of quasi-BICs that occur at low and high temperatures: The first is associated with single Fano resonances, and the last is with several Fano processes. We also discussed possible temperature values and conditions that could be linked with the experimental realization of the results.","PeriodicalId":21682,"journal":{"name":"SciPost Physics","volume":"82 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2024-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142187449","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}

引用次数: 0

Mean-field theory of first-order quantum superconductor-insulator transition 一阶量子超导体-绝缘体转变的均场理论

IF 5.5 2区物理与天体物理

SciPost Physics Pub Date : 2024-08-23 DOI: 10.21468/scipostphys.17.2.066

Igor Poboiko, Mikhail V. Feigel'man

{"title":"Mean-field theory of first-order quantum superconductor-insulator transition","authors":"Igor Poboiko, Mikhail V. Feigel'man","doi":"10.21468/scipostphys.17.2.066","DOIUrl":"https://doi.org/10.21468/scipostphys.17.2.066","url":null,"abstract":"Recent experimental studies on strongly disordered indium oxide films have revealed an unusual first-order quantum phase transition between the superconducting and insulating states (SIT). This transition is characterized by a discontinuous jump from non-zero to zero values of superfluid stiffness at the critical point, contradicting the conventional \"scaling scenario\" typically associated with SIT. In this paper, we present a theoretical framework for understanding this first-order transition. Our approach is based on the concept of competition between two fundamentally distinct ground states that arise from electron pairs initially localized by strong disorder: the superconducting state and the Coulomb glass insulator. These ground states are distinguished by two crucially different order parameters, suggesting a natural expectation of a discontinuous transition between them at $T=0$. This transition occurs when the magnitudes of the superconducting gap $Delta$ and the Coulomb gap $E_C$ become comparable. Additionally, we extend our analysis to low non-zero temperatures and provide a mean-field \"phase diagram\" in the plane of $(T/Delta,E_C/Delta)$. Our results reveal the existence of a natural upper bound for the kinetic inductance of strongly disordered superconductors.","PeriodicalId":21682,"journal":{"name":"SciPost Physics","volume":"59 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2024-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142187441","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}

引用次数: 0

Disordered non-Fermi liquid fixed point for two-dimensional metals at Ising-nematic quantum critical points 二维金属在等静量子临界点的无序非费米液体定点

IF 5.5 2区物理与天体物理

SciPost Physics Pub Date : 2024-08-23 DOI: 10.21468/scipostphys.17.2.059

Kyoung-Min Kim, Ki-Seok Kim

{"title":"Disordered non-Fermi liquid fixed point for two-dimensional metals at Ising-nematic quantum critical points","authors":"Kyoung-Min Kim, Ki-Seok Kim","doi":"10.21468/scipostphys.17.2.059","DOIUrl":"https://doi.org/10.21468/scipostphys.17.2.059","url":null,"abstract":"Understanding the influence of quenched random potential is crucial for comprehending the exotic electronic transport of non-Fermi liquid metals near metallic quantum critical points. In this study, we identify a stable fixed point governing the quantum critical behavior of two-dimensional non-Fermi liquid metals in the presence of a random potential disorder. By performing renormalization group analysis on a dimensional-regularized field theory for Ising-nematic quantum critical points, we systematically investigate the interplay between random potential disorder for electrons and Yukawa-type interactions between electrons and bosonic order-parameter fluctuations in a perturbative epsilon expansion. At the one-loop order, the effective field theory lacks stable fixed points, instead exhibiting a runaway flow toward infinite disorder strength. However, at the two-loop order, the effective field theory converges to a stable fixed point characterized by finite disorder strength, termed the \"disordered non-Fermi liquid (DNFL) fixed point\". Our investigation reveals that two-loop vertex corrections induced by Yukawa couplings are pivotal in the emergence of the DNFL fixed point, primarily through screening disorder scattering. Additionally, the DNFL fixed point is distinguished by a substantial anomalous scaling dimension of fermion fields, resulting in pseudogap-like behavior in the electron's density of states. These findings shed light on the quantum critical behavior of disordered non-Fermi liquid metals, emphasizing the indispensable role of higher-order loop corrections in such comprehension.","PeriodicalId":21682,"journal":{"name":"SciPost Physics","volume":"7 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2024-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142187446","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}

引用次数: 0

On the Virasoro fusion kernel at $c=25$ 关于 $c=25$ 时的维拉索罗聚变内核

IF 5.5 2区物理与天体物理

SciPost Physics Pub Date : 2024-08-22 DOI: 10.21468/scipostphys.17.2.058

Sylvain Ribault, Ioannis Tsiares

引用次数: 0