Radiatively and tunnel-coupled surface electromagnetic waves in metal - dielectric structures

The surface electromagnetic modes in five-layer metal- dielectric structure s are investigated by a numerical computational method. The existence of tw o types of plasmon modes-radiatively and tunnel-coupled-is demonstrated. Th e mode type is determined by the specific geometry of the structure. The re sults of estimates of the effective refractive index of the plasmon leaky m ode excited in an asymmetric three-layer metal-dielectric structure, are pr esented. The optical transparency effect, arising on excitation of the tunn el-coupled surface electromagnetic waves, is demonstrated experimentally.