Rauch Tomáš, Achilles Steven, Henk Jürgen, Mertig Ingrid
Institute of Physics, Martin Luther University Halle-Wittenberg, Von-Seckendorff-Platz 1, 06120 Halle (Saale), Germany.
Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle (Saale), Germany.
Phys Rev Lett. 2015 Jun 12;114(23):236805. doi: 10.1103/PhysRevLett.114.236805.
By means of detailed electronic structure calculations, we show that strained HgTe(x)S(1-x) alloys show a surprisingly rich topological phase diagram. In the strong topological insulator phase, the spin chirality of the topological nontrivial surface states can be reversed by adjusting the alloy concentration x and the strain. On top of this, we predict two semimetallic topological phases, namely, a Dirac semimetal and a Weyl semimetal. The topological phases are characterized by their Z2 invariants and their mirror Chern numbers.
通过详细的电子结构计算，我们表明应变的HgTe(x)S(1-x)合金展现出令人惊讶的丰富拓扑相图。在强拓扑绝缘体相中，通过调整合金浓度x和应变，可以反转拓扑非平凡表面态的自旋手性。除此之外，我们预测了两种半金属拓扑相，即狄拉克半金属和外尔半金属。这些拓扑相由它们的Z2不变量和镜面陈数来表征。
