Electronic and Magnetic Properties of Ferromagnet-Semiconductor Heterostructure Systems

The electronic and magnetic properties of ferromagnet-semiconductor (FM-SC) heterostructure systems have been studied by means of scalar-relativistic KKR-CPA band structure calculations. As a structural model for our calculations periodic multilayer systems have been assumed, taking for the ferromagnet Fe and for the semiconductor GaAs. A justification for the applicability of this geometrical model in describing the electronic and magnetic properties of the real Fe-GaAs-Fe trilayer system is given. Making use of the Coherent Potential Approximation (CPA), the influence of interdiffusion at the Fe-GaAs interface within the multilayer system has been investigated in addition. On the basis of the electronic structure calculations, the magnetic circular X-ray dichroism (MCXD) has been investigated for the L 3 -edges absorption spectra of Ga and As in the near-edge regime (XANES). In both cases the MCXD signal was found to be pronounced enough to be detectable and should motivate corresponding experimental studies.