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

Abstract

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.

15 pages, 7 figures

References in corpus (1)

• Observation of spontaneous spin-splitting in the band structure of an n-type zinc-blende ferromagnetic semiconductor