CONTROL-LASER-INDUCED SUBNATURAL LINEWIDTHS AND QUENCHING OF SPONTANEOUS EMISSION

We show how control lasers lead to subnatural linewidths in spontaneou s emission as well as to the quenching of the quantum noise. We trace this quenching to the dispersive contributions to the line shape. We o btain analytical expressions for linewidths that for boolean AND syste ms are half the natural linewidths with the possibility of much more r eduction for detuned control laser. We further present a simple physic al analysis in terms of a two-photon Fermi golden rule to understand c ancellation of spontaneous emission. Finally, we relate our results to recent experiments.