Investigation of magnetic and electronic coupling between two (Ga,Mn)As layers in (Ga,Mn)As∕GaAs∕(Ga,Mn)As magnetic tunnel junctions

Abstract

The coupling between the two magnetic layers in a series of (Ga,Mn)As∕GaAs∕(Ga,Mn)As magnetic tunnel junctions with different nonmagnetic spacer thicknesses tNM were studied by magnetization and planar Hall effect (PHE) measurements. The PHE data indicate that the magnetization reversals of the two layers are strongly correlated when the tNM is less than 3nm and are independent when tNM is larger than 15nm. From the results, it is concluded that considerable redistribution of hole wave functions plays a major role for small tNM. The PHE results for the sample with 6nm spacer also suggest an antiferromagnetic interlayer exchange coupling.