非互易性和几何 frustrated 性使多体系统避免晶格秩序,表现出复杂液态行为。本文展示其相互作用产生新颖结构和动力学现象,通过非互易耦合的伊辛规范理论,发现 Wilson 环可观测量的线性渐进尺度及准粒子对束缚长度。
摘要:
非互易性和几何 frustrated 性使多体系统避免晶格秩序并表现出复杂、液态行为。本文显示其相互作用比单独部分更丰富,导致意外结构和动力学现象。在最小模型中,两个伊辛规范理论以非互易方式耦合,关键地保持局部 Z_2 对称性。我们发现两个副本的联合 Wilson 环可观测量表现出线性渐进尺度,其准粒子对束缚长度由非互易耦合强度调节。强相互作用诱导的非互易性导致单个解束缚激发的行为,使其在临界渗透簇上运动,遵循自回避路径。将此准粒子动力学映射到磁噪声谱,发现非互易性调节拓扑对数贡献并导致长寿命亚稳态,因准粒子捕获。本文为几何 frustrated 非互易性更广泛研究开辟了道路。
英文摘要:
Non-reciprocity and geometric frustration enable many-body systems to avoid crystalline order and instead exhibit complex, liquid-like behavior. Here we show that their interplay is richer than the sum of its parts, leading to surprising structural and dynamical phenomena. In our minimal model, two copies of Ising gauge theory are non-reciprocally coupled in a way that crucially preserves a local $\mathbb{Z}_2$ symmetry. We discover that the combined Wilson loop observable of the two copies exhibits linear asymptotic scaling, with a quasiparticle-pair confinement length tuned by the strength of the non-reciprocal coupling. Key dynamical features are revealed in the behavior of individual deconfined excitations due to strong interactions induced by the non-reciprocity, leading to motion on a critical percolation cluster that follows a self-avoiding trail. Mapping from this quasiparticle dynamics onto the magnetic noise spectrum, we discover that non-reciprocity tunes topological logarithmic contributions and causes long-lived metastable states due to quasiparticle trapping. Our work opens the way for broader investigations of geometrically frustrated non-reciprocity.
We study classical $J_1$-$J_2$ models with distinct spin degrees of freedom on a honeycomb lattice. For the XY and Heisenberg spins, the system develops a spiral spin liquid (SSL) that is a thermal cooperative paramagnetic regime with spins fluctuating around the spiral contours in the momentum space, and at low temperatures supports a vector spin-chirality order despite the absence of long-range magnetic order. In a strong contrast, for the Ising moments, the low-temperature spin correlation forms a reciprocal "kagomé" structure in the momentum space that resembles the SSL behaviors and persi…
Recently, machine learning has been applied successfully for identifying phases and phase transitions of the Ising models. The continuous phase transition is characterized by spontaneous symmetry breaking, which can not be detected in general from a single spin configuration. To investigate if neural networks can extract correlations among spin snapshots, we propose a new test using the random-gauge Ising model. We show that neural networks can extract the order parameter or the energy of the random-gauge model as in the ferromagnetic case. We also discuss how and where the information of rand…
Motivated by the growing interest in self-correcting quantum memories, we study the feasibility of self-correction in classical lattice systems composed of bounded degrees of freedom with local interactions. We argue that self-correction, including a requirement of stability against external perturbation, cannot be realized in system with broken global symmetries such as the 2d Ising model, but that systems with local, i.e. gauge, symmetries have the required properties. Previous work gave a three-dimensional quantum system which realized a self-correcting classical memory. Here we show that a…
It is known that the normal three-dimensional (3D) Ising model on a cubic lattice is dual to the Wegner's 3D $Z_2$ lattice gauge theory. Here we find an unusual $Z_2$ lattice gauge theory which is dual to the 3D Ising model with not only nearest-neighbor (nn) coupling, but also next-nearest-neighbor (nnn) coupling. Our gauge theory has on each edge four $Z_2$ variables that have product $+1$, each located on a vector perpendicular to the edge. The nn coupling in the Ising model maps to the plaquette term in the gauge theory where the four variables multiplied have their vectors pointing inward…
We discuss a gauged XY model a $θ$-term on an arbitrary lattice in 1+1 dimensions, and show that the theory reduces exactly to the 2d Ising model on the dual lattice in the limit of the strong gauge coupling, provided that the topological term is defined via the Villain action. We discuss the phase diagram by comparing the strong and weak gauge coupling limits, and perform Monte Carlo simulations at intermediate couplings. We generalize the duality to higher-dimensional Ising models using higher-form U(1) gauge field analogues.
On the coupling constant bounds implying area decay of Wilson loop for Z2 lattice gauge theories with Wilson action Boltzmann factor given by bond variables described by transverse Ising model
We present a procedure for reconstructing the decision function of an artificial neural network as a simple function of the input, provided the decision function is sufficiently symmetric. In this case one can easily deduce the quantity by which the neural network classifies the input. The procedure is embedded into a pipeline of machine learning algorithms able to detect the existence of different phases of matter, to determine the position of phase transitions and to find explicit expressions of the physical quantities by which the algorithm distinguishes between phases. We assume no prior k…
Measurements allow efficient preparation of interesting quantum many-body states with long-range entanglement, conditioned on additional transformations based on measurement outcomes. Here, we demonstrate that the so-called conformal quantum critical points (CQCP) can be obtained by performing general single-site measurements in an appropriate basis on the cluster states in $d\geq2$. The equal-time correlators of the said states are described by correlation functions of certain $d$-dimensional classical models at finite temperatures and feature spatial conformal invariance. This establishes an…
Emergent superconformal symmetry in the phase diagram of a 1D $\mathbb{Z}_{2}$ lattice gauge theory
Karlstad University(卡尔斯特大学);Andronikashvili Institute of Physics(安德罗尼卡什维利物理研究所);Ilia State University(伊利亚州立大学);Heinrich-Heine-Universität(海因里希·海涅大学);Nordita, KTH Royal Institute of Technology and Stockholm University(诺迪塔,皇家理工学院与斯德哥尔摩大学)
Griffiths inequalities and Gibbs-Bogoliubov inequality for general gauge glasses with Gaussian disorder on Nishimori line
Graduate School of Information Sciences, Tohoku University(东北大学信息科学研究院);School of Computing, Institute of Science Tokyo(东京科学大学理工学院);Department of Physics, Institute of Science Tokyo(东京科学大学物理系);Research and Education Institute for Semiconductors and Informatics, Kumamoto University(熊本大学半导体与信息教研院);Sigma-i Co., Ltd.(Sigma-i有限公司)