Giant magnetoresistance and super-paramagnetism in Co/Au multilayers

Abstract We present results for the magnetoresistance and magnetisation of MBE grown Co/Au multilayers with very thin Co thicknesses. These multilayers exhibit superparamagnetic properties similar to the non-multilayer granular systems when the Co layer is discontinuous. By controlling the growth rate, it was found that we can vary the Co island size and therefore the blocking temperature of superparamagnetic particles.