Modification of spontaneous emission lifetimes in the presence of corrugated metallic surfaces

We report the results of measurements of the spontaneous emission lifetime of a Eu3+ complex in the presence of a nearby metal surface. The excited-st ate lifetime of the ions are measured as a function of their separation fro m both planar and periodically corrugated metallic surfaces. Several corrug ated silver surfaces were used, each having a different combination of pitc h and amplitude. No significant difference is found between data obtained f or ions situated above a planar silver surface and those above corrugated s urfaces that have pitches greater than the emission wavelength. However, fo r surfaces with a pitch less than the emission wavelength, differences ale seen, and are shown to increase with increasing corrugation amplitude. Poss ible explanations for the observed differences are given, including a discu ssion of the role of surface plasmon polariton modes on corrugated metallic surfaces. [S0163-1829(99)05511-3].