Dual-Gated Graphene Devices for Near-Field Nano-imaging

Graphene-based heterostructures display a variety of phenomena that are strongly tunable by electrostatic local gates. Monolayer graphene (MLG) exhibits surface plasmon polaritons, as revealed scanning nano-infrared experiments. In bilayer (BLG), an electronic gap is induced perpendicular displacement field. Gapped BLG predicted to unusual effects such amplification and domain wall plasmons with significantly larger lifetime than MLG. Furthermore, correlated phases highly sensitive fields have been observed in twisted structures. However, applying experiments has only recently become possible (Ref. 1). this work, we fully characterize two approaches realizing nano-optics compatible top-gates: $\text{MoS}_2$ We perform imaging on both types structures evaluate their strengths weaknesses. Our work paves the way for comprehensive near-field plasmonic graphene-based heterostructures.