Boosting proximity spin orbit coupling in graphene/WSe$_2$ heterostructures via hydrostatic pressure

TL;DR

This study demonstrates that applying hydrostatic pressure to graphene/WSe2 heterostructures enhances proximity-induced spin-orbit coupling, evidenced by a transition from weak localization to weak anti-localization.

Contribution

It shows that hydrostatic pressure can be used to tune and enhance spin-orbit coupling in graphene heterostructures, a novel approach for material engineering.

Findings

Transition from weak localization to weak anti-localization with pressure

Increased induced spin-orbit coupling in graphene

Pressure-dependent modulation of electronic properties

Abstract

Van der Waals heterostructures composed of multiple few layer crystals allow the engineering of novel materials with predefined properties. As an example, coupling graphene weakly to materials with large spin orbit coupling (SOC) allows to engineer a sizeable SOC in graphene via proximity effects. The strength of the proximity effect depends on the overlap of the atomic orbitals, therefore, changing the interlayer distance via hydrostatic pressure can be utilized to enhance the interlayer coupling between the layers. In this work, we report measurements on a graphene/WSe$_2$ heterostructure exposed to increasing hydrostatic pressure. A clear transition from weak localization to weak anti-localization is visible as the pressure increases, demonstrating the increase of induced SOC in graphene.