We propose to engineer time-reversal-invariant topological insulators in two-dimensional (2D) crystals of transition metal dichalcogenides (TMDCs). We note that, at low doping, semiconducting TMDCs under shear strain will develop spin-polarized Landau levels residing in different valleys. We argue that gaps between Landau levels in the range of 10−100 Kelvin are within experimental reach. In addition, we point out that a superlattice arising from a Moir\'e pattern can lead to topologically non-trivial subbands. As a result, the edge transport becomes quantized, which can be probed in multi-terminal devices made using strained 2D crystals and/or heterostructures. The strong d character of valence and conduction bands may also allow for the investigation of the effects of electron correlations on the topological phases.
@article{arxiv.1311.6650,
title = {Quantum Spin Hall Effect in Two-dimensional Crystals of Transition Metal Dichalcogenides},
author = {M. A. Cazalilla and H. Ochoa and F. Guinea},
journal= {arXiv preprint arXiv:1311.6650},
year = {2014}
}
Comments
4+ pages; 2 figures; Supplementary information included in this revision