Surface plasmon resonance sensor with a magneto-optical structure

Due to resonant excitation of surface plasmons, surface plasmon resonance (SPR) sensors combined with ferromagnetic thin films allow an enhancement of the magneto-optical (MO) response. MO-SPR structures with Au/Co/Au sandwiches are theoretically analyzed in transverse configuration by 4×4 matrix algebra. The influence of sandwich film thickness, layer order and Co–Au multilayers on the relative change of the reflectance for p-polarized waves is analyzed. The results show the important role of the incidence angle distribution of the reflectance without magnetic ordering on the MO-SPR response. An optimized geometry and a corresponding feedback are discussed.