We consider a two-level atom driven by modulated light and find that complete population inversion can be induced by light without any resonant frequency component. This is in contrast to the familiar case of monochromatic driving in which complete population inversion is only possible with resonant light. Our results concern experimentally realizable systems, and hence the effect of spontaneous emission is considered. We relate our results to recent work on double quantum wells and hence extend the parameter regime for low-frequency radiation generation

• Received 13 April 1994

DOI:https://doi.org/10.1103/PhysRevA.50.3500