Ab initio calculations of magnetoresistance and interlayer exchange constants of the ferromagnet-semiconductor layered systems Fe/Ge

We report on the results of calculations of the electronic, magnetic, and transport properties of Fe/Ge multilayer systems that are meant to model ferromagnetic (FM)/semiconductor (SC)/FM trilayer systems. On the base of the generalized Bloch theorem we have calculated the electronic structure of a set of spin-spiral structures, which allows us to extract averaged interlayer exchange parameters and their dependence on the width of the semiconductor spacer. The dependence of the dc conductivity and magnetoresistance on the width of the semiconductor layer and the relative angle between the moments of adjacent FM layers has also been investigated. The transport properties are studied on the basis of the Drude model. (C) 2002 American Institute of Physics.