Gated two-dimensional electron gas in magnetic field: nonlinear versus linear regimes

TL;DR

This paper investigates how magnetic fields influence high mobility gated two-dimensional electron gases, revealing unusual effects during current saturation and providing a theoretical model to explain the nonlinear and linear regime behaviors.

Contribution

It offers new insights into magnetic field effects on 2D electron gases and introduces a simple model linking linear and nonlinear regimes in a Hall bar device.

Findings

Magnetic field causes re-distribution of electron density in the channel.

Unusual effects observed near current saturation due to depletion.

Theoretical model successfully explains experimental observations.

Abstract

We study the effect of magnetic field on the properties of a high mobility gated two-dimensional electron gas in a field effect transistor with the Hall bar geometry. When approaching the current saturation when the drain side of the channel becomes strongly depleted, we see a number of unusual effects related to the magnetic field induced re-distribution of the electron density in the conducting channel. The experimental results obtained in the non-linear regime have been interpreted based on the results obtained in the linear regime by a simple theoretical model, which describes quite well our observations.