Dispersion mechanism of surface magnetoplasmons in periodic layered structures

We investigate the dispersion mechanism of surface magnetoplasmons for periodic layered structures in the Voigt configuration. An analytical dispersion relation that retains a similar form with ordinary surface plasmons is obtained. The splitting of surface plasma frequency is accompanied with unequal field strengths of surface modes at the two interfaces and is characterized by a simple dynamic model that recasts the role of magnetic force on to the effective mass. The underlying mechanism is illustrated with the transverse currents induced by the cyclotron motion of electrons, which appears as the typical feature of the dynamic Hall effect. In particular, the acoustical and optical branches exhibit an anticrossing scheme for small filling fractions, due to the like symmetry of modes in the two branches. As the parallel wave number changes, the two interaction branches experience a transition of mode pattern from symmetry to antisymmetry, or vice versa. (C) 2009 Optical Society of America