The vanishing band gap of graphene has long presented challenges for making high-quality quantum point contacts (QPCs) -- the partially transparent p-n interfaces introduced by conventional split-gates tend to short the QPC. This complication has hindered the fabrication of graphene quantum Hall Fabry-P\'erot interferometers, until recent advances have allowed split-gate QPCs to operate utilizing the highly resistive ν=0 state. Here, we present a simple recipe to fabricate QPCs by etching a narrow trench in the graphene sheet to separate the conducting channel from self-aligned graphene side gates. We demonstrate operation of the individual QPCs in the quantum Hall regime, and further utilize these QPCs to create and study a quantum Hall interferometer.
Cite
@article{arxiv.2206.05623,
title = {Graphene-based quantum Hall interferometer with self-aligned side gates},
author = {Lingfei Zhao and Ethan G. Arnault and Trevyn F. Q. Larson and Zubair Iftikhar and Andrew Seredinski and Tate Fleming and Kenji Watanabe and Takashi Taniguchi and Francois Amet and Gleb Finkelstein},
journal= {arXiv preprint arXiv:2206.05623},
year = {2023}
}