Abstract

In recent years there has been a great deal of interest in systems with atomic coherence, including the predictions of lasing without inversion and ultrahigh index of refraction with zero absorption. We are pursuing experiments in atomic rubidium to observe such effects. Following recent theoretical work by M. O. Scully and others, the experiments underway use diode lasers to create an atomic coherence between two closely spaced ground-state levels in Rb by means of a strong Raman pump and to probe another dipole allowed transition with this same ground-state doublet (a A-type configuration). Because of the multilevel nature of rubidium, a variety of optical-pumping and related effects need to be addressed in order to understand fully the experimental results. Current experimental results in the bichromatic (D₁ and D₂ lines) excitation of Rb vapor will be presented with implications for observation of gain without inversion in such a system.

© 1993 Optical Society of America