论文标题
有损失的非热晶格上的量子动力学
Quantum dynamics on a lossy non-Hermitian lattice
论文作者
论文摘要
我们研究了有限的两部分非铁晶格上量子步行者的量子动力学，每当访问两个sublattices之一时，粒子可以以一定的速度泄漏。最初位于非长讯位置上的量子步行者最终将在长度的演变时间后完全消失，并且获得了每个晶胞上衰减概率的分布。在一个制度中，随着与初始位点的距离的增加，结果分布显示出预期的行为。但是，在另一个制度中，我们发现局部衰减概率的产生分布非常违反直觉，其中边缘单位单元格上出现了相对较高的衰减概率群体，而衰减概率却距离量子步行器的起点最远。然后，我们分析具有纯粹损失的非热晶格的能量谱，发现所得衰减概率分布的有趣行为与边缘状态的存在和特定特性密切相关，边缘状态受到拓扑保护，并且可以通过非字体绕组数量进行很好的预测。可以用耦合谐振器光学波导的阵列在实验中观察到外来动力学。
We investigate quantum dynamics of a quantum walker on a finite bipartite non-Hermitian lattice, in which the particle can leak out with certain rate whenever it visits one of the two sublattices. Quantum walker initially located on one of the non-leaky sites will finally totally disappear after a length of evolution time and the distribution of decay probability on each unit cell is obtained. In one regime, the resultant distribution shows an expected decreasing behavior as the distance from the initial site increases. However, in the other regime, we find that the resultant distribution of local decay probability is very counterintuitive, in which a relatively high population of decay probability appears on the edge unit cell which is the farthest from the starting point of the quantum walker. We then analyze the energy spectrum of the non-Hermitian lattice with pure loss, and find that the intriguing behavior of the resultant decay probability distribution is intimately related to the existence and specific property of edge states, which are topologically protected and can be well predicted by the non-Bloch winding number. The exotic dynamics may be observed experimentally with arrays of coupled resonator optical waveguides.
