Abstract

We report the alteration of visible spontaneous emission by atoms coupled to the degenerate modes of a confocal resonator. The partial emission rate into the resonator modes is enhanced by a factor of 19 when the resonator is tuned to the atomic transition frequency and inhibited by a factor of 42 when it is detuned. This results in a fractional increase of 1.6% and decrease of 0.5%, respectively, in the total spontaneous emission rate, which we verify by monitoring changes in the intensity of light emitted out the sides of the resonator as it is tuned.