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Updated: Sep 17, 2025

Fabrication of Gate-tunable Graphene Devices for Scanning Tunneling Microscopy Studies with Coulomb Impurities
Published on: July 24, 2015
Enhanced Phonon-Assisted Tunneling in Metal-Twisted Bilayer Graphene Junctions
Radhika Soni1, Suvronil Datta1, Robin Bajaj2
1Department of Instrumentation and Applied Physics, Indian Institute of Science, Bangalore 560012, India.
Abstract:
We report planar tunneling spectroscopy measurements on metal-WSe2-twisted bilayer graphene heterostructures across a broad range of gate and bias voltages. The observed experimental features are attributed to phonon-assisted tunneling and the significantly high density of states within the moiré bands. A notable finding is the enhanced phonon-assisted tunneling in twisted bilayer graphene compared to Bernal bilayer graphene, which arises from a more relaxed in-plane momentum matching criterion. Theoretical calculations of phonon dispersions enable us to identify low-energy phonon modes in both Bernal and twisted bilayers of graphene, thereby elucidating the underlying mechanism of tunneling. Our results establish planar tunneling as a versatile tool to further understand electron-phonon coupling in twisted van der Waals materials.
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