Abstract
A two-dimensional periodically corrugated silver surface prohibits the propagation of the surface plasmons in all lateral directions. And band gaps are generated in the dispersion relation, named plasmonic band gaps. At the edge of this band gap, surface plasmons are laterally confined as standing waves. We investigate this phenomenon for lasing action by the use of a dye film deposited on a corrugated silver surface. Fluorescence of the dye was strongly enhanced. Indeed, we obtained an enhancement factor 150 for a methyl-red doped poly (methylmethacrylate) film and 3 for an evaporated 4-dicyanomethylene-2-methyl-6-p-dimethyl-aminostyryl-4H-pyran film. We also discuss the conditions under which lasing action may occur.