We report the effect of a coherent drive on transient lasing in three-level λ and ξ configurations (c↔a↔b). We show that the presence of a resonant coherent drive on the a↔c optical transition can yield an order of magnitude enhancement of the output laser energy on a a→b extreme ultraviolet (XUV) or X-ray transition than with no coherent drive. We demonstrate the crucial role of coherence ρac for the laser power enhancement. Contrary to the forward direction (with respect to the pump laser), where forward gain can be enhanced for some choice of the drive Rabi frequency ω c, coherent drive on the ac transition always suppresses the backward gain.
- XUV regime
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)