We demonstrate spin-valve magnetoresistance with a current-in-plane (CIP) configuration in (Ga,Fe)Sb / InAs (thickness $t_\mathrm{ InAs}$ nm) / (Ga,Fe)Sb trilayer heterostructures, where (Ga,Fe)Sb is a ferromagnetic semiconductor (FMS) with high Curie temperature ($T_\mathrm{ C}$). An MR curve with an open minor loop is clearly observed at 3.7 K in a sample with $t_\mathrm{ InAs}$ = 3 nm, which originates from the parallel - antiparallel magnetization switching of the (Ga,Fe)Sb layers and spin-dependent scattering at the (Ga,Fe)Sb / InAs interfaces. The MR ratio increases (from 0.03 to 1.6%) with decreasing $t_\mathrm{ InAs}$ (from 9 to 3 nm) due to the enhancement of the interface scattering. This is the first demonstration of the spin-valve effect in Fe-doped FMS heterostructures, paving the way for device applications of these high- $T_\mathrm{ C}$ FMSs.

Categories: cond-mat.mtrl-sci cond-mat.mes-hall

Current-in-plane spin-valve magnetoresistance in ferromagnetic semiconductor (Ga,Fe)Sb heterostructures with high Curie temperature