en
Scientific article
English

Nanoinfrared Characterization of Bilayer Graphene Conductivity under Dual-Gate Tuning

Published inNano letters, vol. 21, no. 12, p. 5151-5157
Publication date2021-06-01
First online date2021-06-01
Abstract

Dual-gate tuning on two-dimensional (2D) heterostructures can provide independent control of the carrier concentration and interlayer electrostatic potential, yielding novel electronic and optical properties. In this paper, by utilizing monolayer graphene as both the top gate and a plasmon wavelength magnifier, the optical properties of bilayer graphene (BLG) under dual-gate are quantitatively investigated by nanoinfrared imaging. The hybrid optical modes in the vertically coupled two-layer system are imaged from scattering-type scanning near-field microscopy (s-SNOM). Moreover, plasmon dispersion behaviors under varied dual-gate tuning are explored and explained well with theoretical ones employing tight binding approximation, which reveals the flexibility in individually manipulating the Fermi energy and bandgap. Especially, electron–hole asymmetry in BLG is verified from experiments. Our studies pave route for quantitative near-field investigation of superlattice, topological boundaries, and other emergent phenomena in graphene-based 2D heterostructures.

Keywords
  • Bilayer graphene
  • Dual-gate
  • Near-field infrared microscopy
  • Surface plasmons
  • Two-dimensional heterostructures
Research group
Citation (ISO format)
LUO, Weiwei et al. Nanoinfrared Characterization of Bilayer Graphene Conductivity under Dual-Gate Tuning. In: Nano letters, 2021, vol. 21, n° 12, p. 5151–5157. doi: 10.1021/acs.nanolett.1c01167
Main files (1)
Article (Published version)
accessLevelRestricted
Identifiers
ISSN of the journal1530-6984
227views
2downloads

Technical informations

Creation01/04/2022 3:41:00 PM
First validation01/04/2022 3:41:00 PM
Update time03/16/2023 2:16:54 AM
Status update03/16/2023 2:16:54 AM
Last indexation01/29/2024 11:14:21 PM
All rights reserved by Archive ouverte UNIGE and the University of GenevaunigeBlack