论文标题
与稀释障碍的量子旋转链中的定位和降低运输
Localisation and Sub-Diffusive Transport in Quantum Spin Chains With Dilute Disorder
论文作者
论文摘要
人们普遍认为，一个维度的多体定位是脆弱的，很容易被热包裹物摧毁，但是关于局部阶段的稳定性以及在什么条件下，仍然存在许多开放问题。在这里，我构建具有稀释障碍的模型，该模型在翻译不变和完全随机模型之间插值，以研究定位的分解。这打开了可以控制地增加热区域密度并检查定位的可能性，并随着该密度的增加而进行分解。在强障碍下，即使热疗法区域的浓度很高，数值结果也与通常使用的定位诊断一致。在中度疾病中，我提供了跨相图的大区域的缓慢动态和降低运输的证据，暗示了“不良金属”阶段。这表明稀释疾病可能是研究多体定位中的Griffith效应的有用有效模型，也许也可能是在更广泛的无序系统中。
It is widely believed that many-body localisation in one dimension is fragile and can be easily destroyed by thermal inclusions, however there are still many open questions regarding the stability of the localised phase and under what conditions it breaks down. Here I construct models with dilute disorder, which interpolate between translationally invariant and fully random models, in order to study the breakdown of localisation. This opens up the possibility to controllably increase the density of thermal regions and examine the breakdown of localisation as this density is increased. At strong disorder, the numerical results are consistent with commonly-used diagnostics for localisation even when the concentration of thermalising regions is high. At moderate disorder, I present evidence for slow dynamics and sub-diffusive transport across a large region of the phase diagram, suggestive of a `bad metal' phase. This suggests that dilute disorder may be a useful effective model for studying Griffiths effects in many-body localisation, and perhaps also in a wider class of disordered systems.
