Effect of Surface Roughness on Propagation of Surface Plasmon Polaritons Along Thin Lossy Metal Films

In this paper surface plasmon polaritons (SPP) that propagate along thin lossy metal films with surface irregularities are studied. Two cases of metal slab (with infinitewidth) and metal strip (with finite width) are considered. Surface roughness is modelled as a grating with deterministic profile. To analyze the slab structure the method of reducedRayleigh equation is used. The results show that antisymmetric mode is strongly affected with roughness. Accuracy of the resultis demonstrated through comparisons with HFSS simulations. The effect of surface roughness on the metal strip structure isonly simulated by HFSS software. It shows that the attenuation of SPP modes is increased due to the surface roughness

Keywords:

Surface plasmon polaritons (SPP) , reduced Rayleigh equation , surface roughness