Department of Physics, Northeastern University, Boston, Massachusetts 02115, USA.
Phys Rev Lett. 2010 Jul 16;105(3):036404. doi: 10.1103/PhysRevLett.105.036404.
We investigate several strong spin-orbit coupling ternary chalcogenides related to the (Pb,Sn)Te series of compounds. Our first-principles calculations predict the low-temperature rhombohedral ordered phase in TlBiTe₂, TlBiSe₂, and TlSbX₂ (X=Te, Se, S) to be topologically nontrivial. We identify the specific surface termination that realizes the single Dirac cone through first-principles surface state computations. This termination minimizes effects of dangling bonds, making it favorable for photoemission experiments. In addition, our analysis predicts that thin films of these materials could harbor novel 2D quantum spin Hall states, and support odd-parity topological superconductivity.
我们研究了几种与（Pb，Sn）Te 系列化合物相关的强自旋轨道耦合三元硫属化物。我们的第一性原理计算预测，TlBiTe₂、TlBiSe₂ 和 TlSbX₂（X=Te、Se、S）在低温下具有拓扑非平庸的三方有序相。我们通过第一性原理表面态计算确定了实现单个狄拉克锥的特定表面终止。这种终止最小化了悬键的影响，有利于光发射实验。此外，我们的分析预测，这些材料的薄膜可能具有新型的二维量子自旋霍尔态，并支持奇宇称拓扑超导性。
