Spin-orbit proximity in MoS₂/bilayer graphene heterostructures

Area of Science:

• Condensed Matter Physics
• Materials Science
• Nanoscience

Background:

• Van der Waals heterostructures enable tunable electronic properties by integrating 2D materials.
• Bilayer graphene/transition metal dichalcogenide (TMD) interfaces are promising for inducing spin-orbit coupling (SOC) in graphene.

Purpose of the Study:

• To experimentally investigate the nature of SOC in bilayer graphene/TMD heterostructures.
• To understand the influence of SOC on electronic transport phenomena in these systems.

Main Methods:

• Fabrication of heterostructures using bilayer graphene and molybdenum disulfide.
• Experimental measurement of electronic transport properties, including conductivity and magnetoconductivity.
• Analysis of the impact of electric displacement fields on conductivity.

Main Results:

• Confirmation of two distinct SOC types: Ising (1.55 meV) and Rashba (2.5 meV) in bilayer graphene.
• Observation of a non-monotonic conductivity trend at charge neutrality, linked to Ising SOC-induced gaps.
• Discovery of sharp magnetoconductivity peaks near a critical displacement field.

Conclusions:

• The study experimentally verifies the presence and types of SOC in bilayer graphene/TMD interfaces.
• Ising SOC creates tunable single-particle gaps influencing conductivity, challenging current theoretical models.
• Findings provide crucial insights for designing next-generation electronic devices based on tailored SOC effects.