The electronic and magnetoresistive properties of metal/oxide/p-InMnAs magnetic tunnel junctions have been characterized. Ni and Al were each used as the metal electrode, while A12O3 and SiO2 layers were utilized as tunnel barriers. A conductance well, with a width ∼ 100 meV less than the band gap of InMnAs, is observed for all samples, consistent with tunneling between a metal and p-type degenerate semiconductor. At temperatures up to 150 K, a negative magnetoresistance is measured in the tunnel junctions. The absence of the normal tunnel magnetoresistance effect in the Ni-based junctions is attributed to strong interlayer coupling between the ferromagnetic Ni and InMnAs layers.
ASJC Scopus subject areas
- Physics and Astronomy(all)