Magnetotransport properties of GaMnAs based trilayer structures with different thicknesses of InGaAs spacer layer

Magnetotransport properties of GaMnAs/InGaAs/GaMnAs trilayer structures have been investigated by Hall measurements. The samples in the series are identical except for the InGaAs spacer thickness, which varies from 5 to 50 nm. The Hall measurements revealed the systematic change of magnetic easy axes from in-plane to out-of plane with increasing InGaAs spacer thickness. Such dependence of magnetic easy axes of the trilayer systems was understood in terms of the magnetic anisotropy change with spacer thickness. In the magnetization reversal process, various configurations of magnetization between the two GaMnAs layers were observed both in in-plane and out-of plane samples by the planar and the anomalous Hall effects. (C) 2009 American Institute of Physics. [DOI: 10.1063/1.3059601]