Surface magnetoplasmon polaritons in transversely magnetized metal films

Abstract

Surface magnetoplasmon polaritons at the interface between a dielectric and a semiinfinite magnetic metal demonstrate a splitting of the dispersion curve dependent on the propagation direction.1 A thin nonmagnetic metal film bounded symmetrically by a semiconductor supports symmetric and antisymmetric surface magnetoplasmon modes which show a decrease in propagation distance with the application of a transverse magnetic field.2 We consider a thin magnetic metal film bounded symmetrically or near-symmetrically by dielectric media. Dispersion relations for the freely propagating symmetric and antisymmetric modes have been derived for a transverse applied magnetic field. The shift of each mode’s propagation constant due to the applied field depends on the thickness of the metal film. A zero shift is calculated for a certain film thickness, as determined by the metal properties. We also analyze theoretically the excitation of these coupled-surface magnetoplasma waves in an attenuated total reflection (ATR) geometry and compare the results to the Otto and Kretschmann ATR geometries for exciting single-surface magnetoplasma waves.