Electric field tunable spin-orbit gap in a bilayer graphene/WSe${}_2$ quantum dot

Abstract

We report on the investigation of proximity-induced spin-orbit coupling (SOC) in a heterostructure of bilayer graphene (BLG) and tungsten diselenide (WSe${}_2$). A BLG quantum dot (QD) in the few-particle regime acts as a sensitive probe for induced SOC. Finite bias and magnetotransport spectroscopy measurements reveal a significantly enhanced SOC that decreases with the applied displacement field, distinguishing it from pristine BLG. Furthermore, our measurements demonstrate a reduced valley $g$-factor at larger displacement fields, consistent with a weaker lateral confinement of the QD. Our findings show evidence of the influence of WSe${}_2$ across BLG layers, driven by reduced real-space confinement and increased layer localization of the QD states on the BLG layer distant to the WSe${}_2$ at higher displacement fields. This study demonstrates the electrostatic tunability of the spin-orbit gap in BLG/WSe${}_2$ heterostructures, which is especially relevant for the field of spintronics and future spin qubit control in BLG QDs.

7 pages, 5 figures

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Cited by in corpus (2)

• Weak localization as probe of spin-orbit-induced spin-split bands in bilayer graphene proximity coupled to WSe${}_2$
• Tuning proximity-induced spin-orbit coupling in graphene/WSe${}_2$ heterostructures