Spin-dependent magnetotransport in a p-InMnSb/n-InSb magnetic semiconductor heterojunction

The spin-dependent transport properties in p-InMnSb/n-InSb magnetic semiconductor heterojunctions are presented. A positive junction giant magnetoresistance is observed from 75 to 298 K. The magnetoresistance is attributed to conduction via two spin channels resulting from p-d exchange interaction. The magnetoconductance of the heterojunction and its magnetic field dependence are well-described by a two-band model where the bands are spin-polarized. At 75 K and zero field, the spin polarization in the alloy is 90% and decreases to 48% at 298 K. The large spin polarization indicates that InMnSb should be suitable for spin-based transistors that operate at room temperature. (C) 2011 American Institute of Physics. [doi:10.1063/1.3589987]