TAMR effect in (Ga,Mn)As-based tunnel structures

We discuss the results of our experiments on tunnel devices based on (Ga,Mn)As structures. Those include p+-(Ga, Mn)As/n+-GaAs Esaki diodes and laterally defined narrow nanoconstrictions in (Ga,Mn)As epilayers. We found in those structures strong anisotropic magnetoresistance behaviour with features that could be attributed to the novel tunnelling anisotropic magnetoresistance effect. We argue however, that in case of nanoconstricted (Ga,Mn)As wires, some other physics has to be additionally employed to fully explain the observed effects.