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

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