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arXiv · 2011.10198

Dual-gated graphene devices for near-field nano-imaging

Sai S. Sunku·Dorri Halbertal·Rebecca Engelke·Hyobin Yoo·Nathan R. Finney·Nicola Curreli·Guangxin Ni·Cheng Tan·Alexander S. McLeod·Chiu Fan Bowen Lo·Cory R. Dean·James C. Hone·Philip Kim·Dmitri N. Basov
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Abstract

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

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Sai S. Sunku, Dorri Halbertal, Rebecca Engelke, Hyobin Yoo, Nathan R. Finney, Nicola Curreli, Guangxin Ni, Cheng Tan, Alexander S. McLeod, Chiu Fan Bowen Lo, Cory R. Dean, James C. Hone, Philip Kim, Dmitri N. Basov. 2020-11-20. Dual-gated graphene devices for near-field nano-imaging. https://doi.org/10.1021/acs.nanolett.0c04494

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