Abstract

A dye solution (R6G dissolved in propylene carbonate) is placed in a microcavity consisting of two dielectric mirrors, made from alternating layers of silica (n = 1.5) and tantalum pentoxide (n = 2.265). The peak reflectivity of the mirrors is designed to be at 560nm. The top layer of each mirror is silica, deliberately grown 20nm thinner than the λ/4n condition and the microcavity is formed by placing a drop of the dye solution on one mirror, and then pressing the other one on top. The resulting structure is a λ/2n thick microcavity with a dye layer, approximately 40nm thick, at the centre. The spontaneous emission of the dye is enhanced at the cavity resonance but suppressed in the wings. The integrated spontaneous emission is doubled when we use an asymmetric cavity with an output coupler and high reflector and the narrowing of the emission spectrum allows more efficient filtering to remove the pump light.

© 1998 IEEE