Quantum Spin Hall Effect and Topological Field Effect Transistor in Two-Dimensional Transition Metal Dichalcogenides

TL;DR

This paper introduces large-gap quantum spin Hall insulators in 2D transition metal dichalcogenides, demonstrating their tunable topological properties and proposing a novel topological field effect transistor with enhanced conductance and electric switching capabilities.

Contribution

It presents a new class of large-gap quantum spin Hall insulators in 2D TMDCs and proposes a topological FET device architecture utilizing these materials.

Findings

Identification of large-gap QSH insulators in MX2 (M=Mo,W; X=S,Se,Te)

Demonstration of electric field tunability of topological properties

Proposal of a topological FET with enhanced conductance and switching

Abstract

We report a new class of large-gap quantum spin Hall insulators in two-dimensional transition metal dichalcogenides, namely, MX$_2$ with M=(Mo, W) and X=(S, Se, and Te), whose topological electronic properties are highly tunable by external electric field. We propose a novel topological field effect transistor made of these atomic layer materials and their van der Waals heterostructures. Our device exhibits parametrically enhanced charge-spin conductance through topologically protected transport channels, and can be rapidly switched off by electric field through topological phase transition instead of carrier depletion. Our work provides a practical material platform and device architecture for topological quantum electronics.