Abstract

Migration of electronic excitation is an important process influencing population inversion in laser crystals. The light-induced grating (LIG) diffraction technique directly addressing the spatial motion of excitation has been used actively to study energy migration in laser crystals and glasses.^1-4 In LIG diffraction experiments, a transient population grating is created by two mutually coherent laser beams and probed by a third beam. After the pump light is off, the diffraction signal decays exponentially with the decay rate, K, determined by the excitation life-time, τ; angle between the writing beams, Θ; and the diffusion coefficient, D.⁵

© 1996 Optical Society of America