Effect of exit and injection rates on phase-dependent transient evolution of gain without inversion

Abstract:

It is shown that in an open Λ-type system with spontaneously generated coherence, the transient evolution rule of the gain of lasing without inversion (LWI) is very sensitive to variation of the relative phase ϕ between the probe and driving fields; the variety of the atomic exit rate γ₀ and the ratio C of the atomic injection rates also have a considerable effect on the phase-dependent transient evolution rule of LWI gain. We find that when ϕ =0, the transient and stationary LWI gain increases with C increasing but decreases with γ₀ increasing; when ϕ ≠ 0, the effect of C and γ₀ on LWI gain is just opposite to that when ϕ=0; in order to get the largest transient and stationary LWI gain, we need selecting suitable values of ϕ, γ₀ and C. Supported by the National Natural Science Foundation of China (Grant No. 10675076)and the Natural Science Foundation of Shandong Province (Grant No. Y2006A21).