Magneto-resistive memory in ferromagnetic (Ga,Mn)As nanostructures

We show a novel magneto-resistive effect that appears in lithographically shaped, three-arm nanostructure, fabricated from ferromagnetic (Ga,Mn)As layers. The effect, related to a rearrangement of magnetic domain walls between different pairs of arms in the structure, reveals as a dependence of zero-field resistance on the direction of previously applied magnetic field. This effect could allow designing devices with unique switching and memory properties.