Large tunneling magnetoresistance in GaMnAs/AlAs/GaMnAs ferromagnetic semiconductor tunnel junctions
نویسندگان
چکیده
We have observed very large tunneling magnetoresistance (TMR) in epitaxially grown Ga1−xMnxAs/AlAs/Ga1−xMnxAs ferromagnetic semiconductor tunnel junctions. Large TMR ratios more than 70% were obtained in junctions with a very thin (5 1.6 nm) AlAs tunnel barrier when the magnetic field was applied along the [100] axis in the film plane. The TMR was found to rapidly decrease with increasing the barrier thickness, which is explained by calculations assuming that the parallel wavevector of carriers is conserved in tunneling.
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