Hydrostatic pressure study of paramagnetic-ferromagnetic phase transition in (Ga,Mn)As

TL;DR

This study investigates how hydrostatic pressure influences the paramagnetic-ferromagnetic phase transition in (Ga,Mn)As, revealing small but opposite changes in Curie temperature depending on sample resistivity.

Contribution

It provides experimental data on pressure effects on TC in (Ga,Mn)As using resistivity and Hall measurements, highlighting opposite trends in different samples.

Findings

Pressure causes small changes in TC (~1K/GPa).

Changes in TC are opposite for different resistivity samples.

Transport measurements effectively monitor phase transition shifts.

Abstract

The effect of hydrostatic pressure on the paramagnetic - ferromagnetic phase transition has been studied in (Ga,Mn)As. The variation of the Curie temperature (TC) with pressure was monitored by two transport methods: (1) - measurement of zero field resistivity versus temperature {\rho}(T), (2) - dependence on temperature of the Hall voltage hysteresis loop. Two specimens of different resistivity characteristics were examined. The measured pressure-induced changes of TC were relatively small (of the order of 1K/GPa) for both samples, however they were opposite for the two.