title: Quantum spin Hall effect in two-dimensional crystals of transition-metal dichalcogenides.
abstract: We propose to engineer time-reversal-invariant topological insulators in two-dimensional 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 K are within experimental reach. In addition, we point out that a superlattice arising from a moiré pattern can lead to topologically nontrivial subbands. As a result, the edge transport becomes quantized, which can be probed in multiterminal 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.
authors.affiliation: Department of Physics, National Tsing Hua University, and National Center for Theoretical Sciences (NCTS), Hsinchu City, Taiwan and Donostia International Physics Center (DIPC), Manuel de Lardizabal 4, 20018 San Sebastian, Spain.
authors.forename: M A
authors.initials: MA
authors.lastname: Cazalilla
authors.affiliation: Instituto de Ciencia de Materiales de Madrid (ICMM), CSIC, Cantoblanco, E-28049 Madrid, Spain.
authors.forename: H
authors.initials: H
authors.lastname: Ochoa
authors.affiliation: Instituto de Ciencia de Materiales de Madrid (ICMM), CSIC, Cantoblanco, E-28049 Madrid, Spain.
authors.forename: F
authors.initials: F
authors.lastname: Guinea