We investigate the electronic structures of the alloyed Bi1−xSbx compounds based on first-principle calculations including spin-orbit coupling (SOC), and calculate the surface states of semi-infinite systems using maximally localized Wannier function (MLWF). From the calculated results, we analyze the topological nature of Bi1−xSbx, and found the followings: (1) pure Bi crystal is topologically trivial; (2) topologically non-trivial phase can be realized by reducing the strength of SOC via Sb doping; (3) the indirect bulk band gap, which is crucial to realize the true bulk insulating phase, can be enhanced by uniaxial pressure along c axis. (4) The calculated surface states can be compared with experimental results, which confirms the topological nature; (5) We predict the spin-resolved Fermi surfaces and showed the vortex structures, which should be examined by future experiments.
@article{arxiv.0901.2762,
title = {Electronic Structures and Surface States of Topological Insulator Bi$_{1-x}$Sb$_{x}$},
author = {Hai-Jun Zhang and Chao-Xing Liu and Xiao-Liang Qi and Xiao-Yu Deng and Xi Dai and Shou-Cheng Zhang and Zhong Fang},
journal= {arXiv preprint arXiv:0901.2762},
year = {2009}
}