High-frequency conductivity and magnetoreflection of light from magnetic multilayers

We consider the high-frequency conductivity of magnetic multilayers and show that for the high-frequency conductivity there is a giant magnetoresistance effect. The relative change of the high-frequency conductivity for frequencies omega tau similar to 1 has equal imaginary and real parts, where tau is the relaxation time. It is shown that the relative change of the deviation of the reflectivity of magnetic multilayers in the magnetic field from 1 is large and that a magnetic multilayer is a dispersive magnetic mirror, which is controlled by the magnetic field and the relative change of the reflectivity of light is frequency dependent. (C) 1998 Elsevier Science B.V.