Exchange interaction and Curie temperature in Ge1-xMn xTe ferromagnetic semiconductors

Abstract

We present the magnetotransport studies of Ge1-xMnxTe ferromagnetic semiconductor under hydrostatic pressure. The investigation of the normal and Hall resistivities provide an insight to the dependence of carrier concentration, mobility, and magnetic properties on pressure. Our results reveal that the application of pressure changes the band structure, which can be explained by a two valence band model. We observe the enhancement and reduction of Curie temperature within a pressure range of 0-24 kbar. Analysis within the framework of the Ruderman-Kittel-Kasuya-Yosida model allows us to identify the factors in controlling the Tc, in which the exchange interaction plays a predominant role in the formation of ferromagnetic phase. © 2011 American Institute of Physics.