arXiv: Statistical Mechanics最新文献_第6页

Dissipative dynamics at first-order quantum transitions 一阶量子跃迁的耗散动力学

arXiv: Statistical Mechanics Pub Date : 2020-09-23 DOI: 10.1103/physrevb.102.224302

G. Di Meglio, D. Rossini, E. Vicari

引用次数: 8

Measurement and Entanglement Phase Transitions in All-To-All Quantum Circuits, on Quantum Trees, and in Landau-Ginsburg Theory 全对全量子电路、量子树和朗道-金斯堡理论中的测量和纠缠相变

arXiv: Statistical Mechanics Pub Date : 2020-09-23 DOI: 10.1103/PRXQUANTUM.2.010352

A. Nahum, S. Roy, B. Skinner, J. Ruhman

{"title":"Measurement and Entanglement Phase Transitions in All-To-All Quantum Circuits, on Quantum Trees, and in Landau-Ginsburg Theory","authors":"A. Nahum, S. Roy, B. Skinner, J. Ruhman","doi":"10.1103/PRXQUANTUM.2.010352","DOIUrl":"https://doi.org/10.1103/PRXQUANTUM.2.010352","url":null,"abstract":"Quantum many-body systems subjected to local measurements at a nonzero rate can be in distinct dynamical phases, with differing entanglement properties. We introduce theoretical approaches to measurement-induced phase transitions (MPT) and also to entanglement transitions in random tensor networks. Many of our results are for \"all-to-all\" quantum circuits with unitaries and measurements, in which any qubit can couple to any other, and related settings where some of the complications of low-dimensional models are reduced. We also propose field theory descriptions for spatially local systems of finite dimensionality. To build intuition, we first solve the simplest \"minimal cut\" toy model for entanglement dynamics in all-to-all circuits, finding scaling forms and exponents within this approximation. We then show that certain all-to-all measurement circuits allow exact results by exploiting the circuit's local tree-like structure. For this reason, we make a detour to give universal results for entanglement phase transitions in a class of random tree tensor networks, making a connection with the classical theory of directed polymers on a tree. We then compare these results with numerics in all-to-all circuits, both for the MPT and for the simpler \"Forced Measurement Phase Transition\" (FMPT). We characterize the two different phases in all-to-all circuits using observables that are sensitive to the amount of information propagated between the initial and final time. We demonstrate signatures of the two phases that can be understood from simple models. Finally we propose Landau-Ginsburg-Wilson-like field theories for the MPT, the FMPT, and for entanglement transitions in tensor networks. This analysis shows a surprising difference between the MPT and the other cases. We discuss variants of the measurement problem with additional structure, and questions for the future.","PeriodicalId":8473,"journal":{"name":"arXiv: Statistical Mechanics","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85816905","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: 103

Thermodynamic Casimir forces in strongly anisotropic systems within the $Nto infty$ class $Nto infty$类中强各向异性系统中的热力学卡西米尔力

arXiv: Statistical Mechanics Pub Date : 2020-09-22 DOI: 10.21468/SCIPOSTPHYSCORE.4.2.016

Maciej Lebek, P. Jakubczyk

引用次数: 2

The Folded Spin-1/2 XXZ Model: I. Diagonalisation, Jamming, and Ground State Properties 折叠自旋1/2 XXZ模型:1 .对角化、干扰和基态性质

arXiv: Statistical Mechanics Pub Date : 2020-09-10 DOI: 10.21468/SCIPOSTPHYSCORE.4.2.010

Lenart Zadnik, M. Fagotti

引用次数: 42

Hamiltonian memory: An erasable classical bit 哈密顿记忆:一种可擦除的经典位

arXiv: Statistical Mechanics Pub Date : 2020-09-02 DOI: 10.1103/PHYSREVRESEARCH.3.013232

Roi Holtzman, Geva Arwas, O. Raz

引用次数: 2

Study of the Ashkin Teller model with spins S = 1 and σ = 3/2 subjected to different crystal fields using the Monte-Carlo method 用蒙特卡罗方法研究了自旋为S = 1和σ = 3/2的Ashkin Teller模型在不同晶体场作用下的特性

arXiv: Statistical Mechanics Pub Date : 2020-09-01 DOI: 10.5488/CMP.23.33707

Z. Amimer, S. Bekhechi, B. N. Brahmi, R. Boudefla, H. Ez‐zahraouy, A. Rachadi

引用次数: 1

Critical properties of the Floquet time crystal within the Gaussian approximation 高斯近似下Floquet时间晶体的临界性质

arXiv: Statistical Mechanics Pub Date : 2020-08-24 DOI: 10.1103/PHYSREVB.103.014305

M. Natsheh, A. Gambassi, A. Mitra

{"title":"Critical properties of the Floquet time crystal within the Gaussian approximation","authors":"M. Natsheh, A. Gambassi, A. Mitra","doi":"10.1103/PHYSREVB.103.014305","DOIUrl":"https://doi.org/10.1103/PHYSREVB.103.014305","url":null,"abstract":"The periodically driven O(N) model is studied near the critical line separating a disordered paramagnetic phase from a period doubled phase, the latter being an example of a Floquet time crystal. The time evolution of one-point and two-point correlation functions are obtained within the Gaussian approximation and perturbatively in the drive amplitude. The correlations are found to show not only period doubling, but also power-law decays at large spatial distances. These features are compared with the undriven O(N) model in the vicinity of the paramagnetic-ferromagnetic critical point. The algebraic decays in space are found to be qualitatively different in the driven and the undriven cases. In particular, the spatio-temporal order of the Floquet time crystal leads to position-momentum and momentum-momentum correlation functions which are more long-ranged in the driven than in the undriven model. The light-cone dynamics associated with the correlation functions is also qualitatively different as the critical line of the Floquet time crystal shows a light-cone with two distinct velocities, with the ratio of the two velocities scaling as the square-root of the dimensionless drive amplitude. The Floquet unitary, which describes the time evolution due to a complete cycle of the drive, is constructed for modes with small momenta compared to the drive frequency, but having a generic relationship with the square-root of the drive amplitude. At intermediate momenta, which are large compared to the square-root of the drive amplitude, the Floquet unitary is found to simply rotate the modes. On the other hand, at momenta which are small compared to the square-root of the drive amplitude, the Floquet unitary is found to primarily squeeze the modes, to an extent which increases upon increasing the wavelength of the modes, with a power-law dependence on it.","PeriodicalId":8473,"journal":{"name":"arXiv: Statistical Mechanics","volume":"149 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91519295","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: 11

A generalized q growth model based on nonadditive entropy 基于非加性熵的广义q增长模型

arXiv: Statistical Mechanics Pub Date : 2020-08-18 DOI: 10.1142/s0217979220502811

I. Rond'on, O. Sotolongo-Costa, J. Gonz'alez

引用次数: 2

Thermodynamic uncertainty relation for systems with unidirectional transitions 单向跃迁系统的热力学不确定关系

arXiv: Statistical Mechanics Pub Date : 2020-08-16 DOI: 10.1103/PHYSREVRESEARCH.3.013273

Arnab K. Pal, S. Reuveni, Saar Rahav

{"title":"Thermodynamic uncertainty relation for systems with unidirectional transitions","authors":"Arnab K. Pal, S. Reuveni, Saar Rahav","doi":"10.1103/PHYSREVRESEARCH.3.013273","DOIUrl":"https://doi.org/10.1103/PHYSREVRESEARCH.3.013273","url":null,"abstract":"We derive a thermodynamic uncertainty relation (TUR) for systems with unidirectional transitions. The uncertainty relation involves a mixture of thermodynamic and dynamic terms. Namely, the entropy production from bidirectional transitions, and the net flux of unidirectional transitions. The derivation does not assume a steady-state, and the results apply equally well to transient processes with arbitrary initial conditions. As every bidirectional transition can also be seen as a pair of separate unidirectional ones, our approach is equipped with an inherent degree of freedom. Thus, for any given system, an ensemble of valid TURs can be derived. However, we find that choosing a representation that best matches the systems dynamics over the observation time will yield a TUR with a tighter bound on fluctuations. More precisely, we show a bidirectional representation should be replaced by a unidirectional one when the entropy production associated with the transitions between two states is larger than the sum of the net fluxes between them. Thus, in addition to offering TURs for systems where such relations were previously unavailable, the results presented herein also provide a systematic method to improve TUR bounds via physically motivated replacement of bidirectional transitions with pairs of unidirectional transitions. The power of our approach and its implementation are demonstrated on a model for random walk with stochastic resetting and on the Michaelis-Menten model of enzymatic catalysis.","PeriodicalId":8473,"journal":{"name":"arXiv: Statistical Mechanics","volume":"77 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87161440","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: 23

Convolutional restricted Boltzmann machine aided Monte Carlo: An application to Ising and Kitaev models 卷积受限玻尔兹曼机辅助蒙特卡罗:在Ising和Kitaev模型中的应用

arXiv: Statistical Mechanics Pub Date : 2020-08-12 DOI: 10.1103/physrevb.102.195148

Daniel Alcalde Puente, I. Eremin

引用次数: 4