论文标题
经典随机弗雷德金链中的缓慢动力和较大的偏差
Slow dynamics and large deviations in classical stochastic Fredkin chains
论文作者
论文摘要
弗雷德金自旋链是量子哈密顿量的一个有趣的理论例子,其基态在三个不同的阶段之间表现出相变,其中一个违反了该地区定律。在这里,我们考虑了弗雷德金模型的经典随机版本,可以将其视为受额外动力学约束的简单排除过程,并研究其经典随机动力学。量子链的基态相变表示随机问题中的平衡相变,我们根据数值矩阵乘积状态(MPS)进行了量化其特性。随机模型显示缓慢的动力学,包括衰减自相关功能的功率定律和由于指数定位而导致的分层松弛过程。像其他动力学约束模型一样,弗雷德金链在其动力学大偏差中具有丰富的结构 - 我们通过数值MP进行准确计算,包括活性 - 活性相变,以及连接到模型特定平衡状态的轨迹阶段的层次结构。我们还通过其高度场表示,就蜂窝晶格的约束二聚体覆盖物而言,弗雷德金模型对二维的概括。
The Fredkin spin chain serves as an interesting theoretical example of a quantum Hamiltonian whose ground state exhibits a phase transition between three distinct phases, one of which violates the area law. Here we consider a classical stochastic version of the Fredkin model, which can be thought of as a simple exclusion process subject to additional kinetic constraints, and study its classical stochastic dynamics. The ground state phase transition of the quantum chain implies an equilibrium phase transition in the stochastic problem, whose properties we quantify in terms of numerical matrix product states (MPS). The stochastic model displays slow dynamics, including power law decaying autocorrelation functions and hierarchical relaxation processes due to exponential localization. Like in other kinetically constrained models, the Fredkin chain has a rich structure in its dynamical large deviations - which we compute accurately via numerical MPS - including an active-inactive phase transition, and a hierarchy of trajectory phases connected to particular equilibrium states of the model. We also propose, via its height field representation, a generalization of the Fredkin model to two dimensions in terms of constrained dimer coverings of the honeycomb lattice.