Hall field-induced resistance oscillations in Ge/SiGe quantum wells

TL;DR

This study observes Hall field-induced resistance oscillations in high-mobility Ge/SiGe quantum wells, revealing how dc electric fields influence magnetotransport properties in 2D hole gases.

Contribution

First demonstration of HIRO in Ge/SiGe quantum wells, linking oscillation peaks to hole effective mass and extending understanding of nonlinear transport in 2D hole systems.

Findings

Hall field-induced resistance oscillations observed in Ge/SiGe quantum wells

Peak positions match theoretical predictions using hole effective mass

Oscillations are influenced by applied dc bias and microwave radiation

Abstract

We report on a magnetotransport study in a high-mobility 2D hole gas hosted in a pure Ge/SiGe quantum well subject to dc electric fields and high frequency microwave radiation. We find that under applied dc bias the differential resistivity exhibits a pronounced maximum at a magnetic field which increases linearly with the applied current. We associate this maximum with the fundamental peak of Hall field-induced resistance oscillations (HIRO) which are known to occur in 2D electron gases in GaAs/AlGaAs systems. After taking into account the Dingle factor correction, we find that the position of the HIRO peak is well described by the hole effective mass $m^\star \approx 0.09\,m_0$, obtained from microwave photoresistance in the same sample.