论文标题
旋转链中几乎强边模式的动力学远离集成性
Dynamics of almost strong edge modes in spin chains away from integrability
论文作者
论文摘要
结果显示了几乎强边模式的动力学，该动力学是在不可融合旋转链中发生的准稳定Majorana边缘模式。使用精确的对角线化研究了边缘模式的动力学，并与随时间进化相对于从递归方法获得的Krylov空间中的有效半无限模型进行了比较。发现有效的Krylov Hamiltonian类似于空间不均匀的SSH模型，在该模型中，跳跃幅度随着散装系统的距离而典型，但在其上叠加了隔开或二聚体结构。边缘模式的非扰动寿命被证明是由于这种交错的结构造成的，从而降低了线性增长的跳跃振幅的有效性。在采用Krylov Hamiltonian的连续限制时，发现边缘模式等同于半线上的Dirac Hamiltonian的准稳定模式，其质量在有限的距离内非零，然后终止于无间隙的金属体积。发现分析估计与边缘模式的数值获得的寿命非常吻合。
Results are presented for the dynamics of an almost strong edge mode which is the quasi-stable Majorana edge mode occurring in non-integrable spin chains. The dynamics of the edge mode is studied using exact diagonalization, and compared with time-evolution with respect to an effective semi-infinite model in Krylov space obtained from the recursion method. The effective Krylov Hamiltonian is found to resemble a spatially inhomogeneous SSH model where the hopping amplitude increases linearly with distance into the bulk, typical of thermalizing systems, but also has a staggered or dimerized structure superimposed on it. The non-perturbatively long lifetime of the edge mode is shown to be due to this staggered structure which diminishes the effectiveness of the linearly growing hopping amplitude. On taking the continuum limit of the Krylov Hamiltonian, the edge mode is found to be equivalent to the quasi-stable mode of a Dirac Hamiltonian on a half line, with a mass which is non-zero over a finite distance, before terminating into a gapless metallic bulk. The analytic estimates are found to be in good agreement with the numerically obtained lifetimes of the edge mode.
