Orth Christoph P, Sekera Tibor, Bruder Christoph, Schmidt Thomas L
Department of Physics, University of Basel, Klingelbergstrasse 82, 4056 Basel, Switzerland.
Physics and Materials Science Research Unit, University of Luxembourg, L-1511 Luxembourg.
Sci Rep. 2016 Apr 5;6:24007. doi: 10.1038/srep24007.
It has been proposed that adding disorder to a topologically trivial mercury telluride/cadmium telluride (HgTe/CdTe) quantum well can induce a transition to a topologically nontrivial state. The resulting state was termed topological Anderson insulator and was found in computer simulations of the Bernevig-Hughes-Zhang model. Here, we show that the topological Anderson insulator is a more universal phenomenon and also appears in the Kane-Mele model of topological insulators on a honeycomb lattice. We numerically investigate the interplay of the relevant parameters, and establish the parameter range in which the topological Anderson insulator exists. A staggered sublattice potential turns out to be a necessary condition for the transition to the topological Anderson insulator. For weak enough disorder, a calculation based on the lowest-order Born approximation reproduces quantitatively the numerical data. Our results thus considerably increase the number of candidate materials for the topological Anderson insulator phase.
有人提出,在拓扑平凡的碲化汞/碲化镉(HgTe/CdTe)量子阱中引入无序可以诱导向拓扑非平凡态的转变。由此产生的状态被称为拓扑安德森绝缘体,并且在Bernevig-Hughes-Zhang模型的计算机模拟中被发现。在这里,我们表明拓扑安德森绝缘体是一种更普遍的现象,并且也出现在蜂窝晶格上拓扑绝缘体的Kane-Mele模型中。我们通过数值研究了相关参数之间的相互作用,并确定了拓扑安德森绝缘体存在的参数范围。结果表明,交错子晶格势是向拓扑安德森绝缘体转变的必要条件。对于足够弱的无序,基于最低阶玻恩近似的计算定量地再现了数值数据。因此,我们的结果大大增加了拓扑安德森绝缘体相的候选材料数量。