Abstract
We utilize the effect of hydrostatic pressure to investigate the magnetotransport properties of degenerate p-Ge1-xMnxTe (x=0.10) ferromagnetic semiconductor. The Curie temperature was found to increase with pressure as 0.27 K/kbar, which can be understood on the basis of the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction mechanism. For sufficiently high carrier concentration of p(o)similar to 10(21) cm(-3), both the light holes from the L valence band and the heavy holes from the Sigma valence band contribute to the RKKY interaction. Additionally, a negative magnetoresistance is observed at low temperature and is found to decrease with pressure.