Spin-orbit proximity in MoS<sub>2</sub>/bilayer graphene heterostructures.

Masseroni, Michele; Gull, Mario; Panigrahi, Archisman; Jacobsen, Nils; Fischer, Felix; Tong, Chuyao; Gerber, Jonas D; Niese, Markus et al. · Nat Commun · 2024

basic_science · Level V

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Abstract

Van der Waals heterostructures provide a versatile platform for tailoring electronic properties through the integration of two-dimensional materials. Among these combinations, the interaction between bilayer graphene and transition metal dichalcogenides (TMDs) stands out due to its potential for inducing spin-orbit coupling (SOC) in graphene. Future devices concepts require the understanding of the precise nature of SOC in TMD/bilayer graphene heterostructures and its influence on electronic transport phenomena. Here, we experimentally confirm the presence of two distinct types of SOC - Ising (Δ<sub>I</sub> = 1.55 meV) and Rashba (Δ<sub>R</sub> = 2.5 meV) - in bilayer graphene when interfaced with molybdenum disulfide. Furthermore, we reveal a non-monotonic trend in conductivity with respect to the electric displacement field at charge neutrality. This phenomenon is ascribed to the existence of single-particle gaps induced by the Ising SOC, which can be closed by a critical displacement field. Our findings also unveil sharp peaks in the magnetoconductivity around the critical displacement field, challenging existing theoretical models.