Patrick Kristian, Neupert Titus, Pachos Jiannis K
School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United Kingdom.
Department of Physics, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland.
Phys Rev Lett. 2017 Jun 30;118(26):267002. doi: 10.1103/PhysRevLett.118.267002. Epub 2017 Jun 29.
Very few topological systems with long-range couplings have been considered so far due to our lack of analytic approaches. Here we extend the Kitaev chain, a 1D quantum liquid, to infinite-range couplings and study its topological properties. We demonstrate that, even though topological phases are intimately linked to the notion of locality, the infinite-range couplings give rise to topological zero and nonzero energy Majorana end modes depending on the boundary conditions of the system. We show that the analytically derived properties are to a large degree stable against modifications to decaying long-range couplings. Our work opens new frontiers for topological states of matter that are relevant to current experiments, where systems with interactions of variable range can be designed.
由于缺乏解析方法，到目前为止，很少有人考虑具有长程耦合的拓扑系统。在这里，我们将一维量子液体——基塔耶夫链扩展到无限范围耦合，并研究其拓扑性质。我们证明，尽管拓扑相与局域性概念密切相关，但无限范围耦合会根据系统的边界条件产生拓扑零能和非零能马约拉纳端模式。我们表明，通过解析得出的性质在很大程度上对于衰减长程耦合的修改是稳定的。我们的工作为与当前实验相关的拓扑物态开辟了新的前沿领域，在这些实验中，可以设计具有可变范围相互作用的系统。
