Ballistic hot-electron transport in a quantum Hall edge channel defined by a double gate

TL;DR

This study demonstrates control over hot-electron ballistic transport in a quantum Hall edge channel using a double gate, revealing enhanced ballistic length by tailoring the edge potential to reduce phonon scattering.

Contribution

It introduces a double gate technique to manipulate the edge potential profile, significantly improving ballistic length by suppressing phonon scattering in quantum Hall systems.

Findings

Ballistic length is increased by tailoring the edge potential.

Reducing LO phonon scattering enhances electron transport.

Double gate control effectively modulates the edge potential profile.

Abstract

Ballistic transport of hot electrons in a quantum Hall edge channel is attractive for studying electronic analog of quantum optics, where the edge potential profile is an important parameter that governs the charge velocity and scattering by longitudinal-optical (LO) phonons. Here we use a parallel double gate to control the electric field of the edge potential, and investigate the ballistic length of the channel by using hot-electron spectroscopy. The ballistic length is significantly enhanced by reducing the LO phonon scattering rate in the tailored potential.