Abstract

In 1946 Purcell showed that the spontaneous emission rate of an atomic system could be enhanced by placing it in a conducting cavity. Later, Kleppner showed that spontaneous emission could also be inhibited if the vacuum modes coupled to the atom were excluded by a structure. Most recently, we experimentally have shown that a periodic dielectric structure could alter the spontaneous emission by Bragg scattering of vacuum fluctuations.¹ The structure used was a colloidal crystal with a face-centered cubic structure whose (111) planes were separated by optical dimensions.

© 1990 Optical Society of America