Reversibly switching interlayer exchange coupling (IEC) of magnetic semiconductor multilayers between ferromagnetic (FM) and antiferromagnetic (AFM) modes is a difficult but key issue for fabricating semiconductor giant magnetoresistance devices. Here, we show that such tunable IEC is achievable around room temperature in Co-doped TiO2/VO2 diluted magnetic semiconductor multilayers. On the basi...

We study the spectral shape and the magnetic field induced polarization of hot-electron photoluminescence from the diluted magnetic semiconductor Ga,Mn As. It is demonstrated that the holes occupy predominantly the impurity band and not the valence band as required for the Rudermann-Kittel-Kasuya-Yosida-type exchange interaction. We show that the ground state of the impurity band is split by un...