Excitation Pulse Energy Dependence of Gain Volume in Amplifying and Scattering Medium

Abstract

The excitation pulse energy dependence of the gain volume in an amplifying and scattering medium was examined using a two-beam spatial-correlation method. The volume increased with 1/3 power of the excitation pulse energy in the weak excitation region, and then approached a critical value when the excitation energy was further increased. Numerical simulations explain the experimental results well, and a phenomenological model dealing with the total excitation in the gain volume via a rate equation is also discussed in order to explain the dependence.