Fachgruppe Nanostrukturierte Materialien    

We demonstrate tunnel magnetoresistance junctions based on a trilayer system consisting of an epitaxialNiMnSb, an aluminum oxide, and a CoFe trilayer. The junctions show a tunnelingmagnetoresistance of of 8.7% at room temperature which increases to 14.7% at 4.2K. The layers show a clear separate switching and a small ferromagnetic coupling. A uniaxial in-plane anisotropy in the NiMnSb layer leads to different switching characteristics depending on the direction in which the magnetic field is applied, an effect which can be used for sensor applications.