Low-temperature, in situ tunable, uniaxial stress measurements in semiconductors using a piezoelectric actuator

TL;DR

This paper presents a method using a piezoelectric actuator to apply and tune uniaxial stress at low temperatures in semiconductor quantum wells, enabling control over electronic properties with minimal hysteresis at cryogenic temperatures.

Contribution

It introduces a low-temperature, in situ tunable uniaxial stress technique in semiconductors using a piezoelectric actuator, with detailed strain measurements across temperatures.

Findings

Strain is nearly linear at 4.2 K with minimal hysteresis.

Hysteresis is pronounced at 300 and 77 K.

The method allows continuous tuning of electronic properties via stress.

Abstract

We demonstrate the use of a piezoelectric actuator to apply, at low temperatures, uniaxial stress in the plane of a two-dimensional electron system confined to a modulation-doped AlAs quantum well. Via the application of stress, which can be tuned in situ and continuously, we control the energies and occupations of the conduction-band minima and the electronic properties of the electron system. We also report measurements of the longitudinal and transverse strain versus bias for the actuator at 300, 77, and 4.2 K. A pronounced hysteresis is observed at 300 and 77 K, while at 4.2 K, strain is nearly linear and shows very little hysteresis with the applied bias.