Asymmetric magnetoresistance in a double magnetic barrier device

Abstract

We have obtained a large and quite asymmetric magnetoresistance in a InAs two-dimensional electron gas system in which the shape of the magnetic field profile has the form of two barriers with opposite signs. These magnetic barriers are controlled by a magnetization of micromagnets on the surface of the device. From a numerical analysis based on a diffusive and a ballistic transport model, the mechanism of the asymmetric magnetoresistance effect can be understood in terms of the junction of positive and negative magnetic-field regions. This device can be a good candidate for a magnetoresistance-based device for high-density data storage and retrieval and for a spintronic device using a spin up/down junction.