Graphene-Based Quantum Hall Interferometer with Self-Aligned Side Gates

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 circuit the QPCs. This complication has hindered the fabrication of graphene quantum Hall Fabry-Perot interferometers, until recent advances have allowed split-gate QPCs to operate utilizing the highly resistive v = 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.

Automated summary

The vanishing band gap of graphene has posed challenges for creating high-quality quantum point contacts. However, recent advances have allowed split-gate QPCs to operate using the highly resistive v = 0 state. Researchers have developed a simple method of fabricating QPCs by etching a narrow trench in the graphene sheet, separating the conducting channel from self-aligned graphene side gates. This technique has enabled the creation and study of a quantum Hall interferometer.