Transition-metal dichalcogenide bilayers: Switching materials for spintronic and valleytronic applications

Zibouche N, Philipsen P, Kuc A, Heine T (2014)

Publication Type: Journal article

Publication year: 2014

Journal

Physical Review B - Condensed Matter and Materials Physics American Physical Society (APS)

Book Volume: 90

Article Number: 125440

Journal Issue: 12

DOI: 10.1103/PhysRevB.90.125440

Abstract

We report that an external electric field applied normal to bilayers of transition-metal dichalcogenides TX2(T = Mo, W, X = S, Se) creates significant spin-orbit splittings and reduces the electronic band gap linearly with the field strength. Contrary to the TX2monolayers, spin-orbit splittings and valley polarization are absent in bilayers due to the presence of inversion symmetry. This symmetry can be broken by an electric field, and the spin-orbit splittings in the valence band quickly reach values similar to those in the monolayers (145 meV for MoS2,..., 418 meV for WSe2) at saturation fields less than 500 mV Å^-1. The band gap closure results in a semiconductor-metal transition at field strength between 1.25 (WX2) and 1.50 (MoX2) V Å^-1. Thus, by using a gate voltage, the spin polarization can be switched on and off in TX2bilayers, thus activating them for spintronic and valleytronic applications.

Involved external institutions

Jacobs University Bremen gGmbH

Germany (DE)

How to cite

APA:

Zibouche, N., Philipsen, P., Kuc, A., & Heine, T. (2014). Transition-metal dichalcogenide bilayers: Switching materials for spintronic and valleytronic applications. Physical Review B - Condensed Matter and Materials Physics, 90(12). https://doi.org/10.1103/PhysRevB.90.125440

MLA:

Zibouche, Nourdine, et al. "Transition-metal dichalcogenide bilayers: Switching materials for spintronic and valleytronic applications." Physical Review B - Condensed Matter and Materials Physics 90.12 (2014).

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