Asymmetries between absorption and stimulated emission in driven three-level systems - art. no. 063804

We present a physical picture explaining the asymmetries between absorption and stimulated emission occurring in the driven three-level systems. Based on a dressed-state picture, we obtain transition rates for absorption and stimulated emission separately, and show that the cancellation of absorptio n in the Lambda- and V-type systems are originated from different physical mechanisms. Furthermore, a simple analogy can be applied to cascade-type sy stems to show the absorption enhancement at two-photon resonance.