Abstract

A single molecule in a crystal matrix is a very good example of an electronic two-level system [1]. We illustrate some well-known and some less usual effects of the interaction between an electronic two-level and a laser field with a new system, dibenz-anthanthrene in a naphthalene crystal [2]. We studied the optical saturation of the molecule, and the bunching of fluorescence photons due to a metastable triplet manifold, in which we could resolve two triplet sublevels. The triplet population rates and triplet lifetimes are so low that the bottleneck effect of the triplet may be neglected. We also observed variations of the single molecule radiative linewidths, which we attribute to spontaneous emission modifications by surface effects [2].

© 1998 IEEE