Magneto-optic polar Kerr and Faraday effects in periodic multilayers

Magnetooptic (MO) effects in magnetic multilayers with periodically stratif ied regions are analyzed for the case of normal light wave incidence and po lar magnetization (Faraday and polar Kerr effects). From the universal 4 x 4-matrix formalism simplified analytical representations restricted to term s linear in the off-diagonal permittivity tensor elements are obtained with no loss in accuracy. The MO effects are expressed as weighted sums of cont ributions from individual layers. Approximate expressions useful for the ev aluation of trends in MO effects are given for periodic multilayers consist ing of blocks with ultrathin magnetic lms. The procedure is illustrated on periodic systems built of symmetric units. Limits on the ultrathin approxim ation are discussed. (C) 2001 Optical Society of America.