Abstract

A few years ago, many people would have deemed the optical observation of single molecules nearly impossible. Yet, new experiments at room [1] and at liquid helium temperatures [2,3] have started to remove this psychological barrier. Several applications to trace detection and sensing, to spectroscopy of localized neighborhoods and to optical addressing of local spots in solids may now be envisioned. The purpose of this presentation is to show that single molecules can be studied at helium temperatures by means of a fairly simple setup, at least in the very favorable case of pentacene in terphenyl crystal. We thus hope to stimulate further work either on this model system or on more difficult ones with more sophisticated detection methods.

© 1991 Optical Society of America