ENHANCED BACKSCATTERING OF SURFACE-POLARITONS ON A RANDOMLY ROUGH-SURFACE

We present a theory of the enhanced backscattering of surface polarito ns on a two-dimensional randomly rough surface. We solve the scatterin g problem by the method of reduced Rayleigh equations using unitary an d reciprocal expansions in powers of the surface profile function. We calculate the angular dependence of the intensity of the surface polar itons into which the incident surface polariton has been scattered, an d find that it has a peak in the backscattering direction. The effect is expected to be most easily observed by the methods of near-field op tical microscopy in the infrared range. [S0163-1829(98)01507-0].