Study of nonlinear effects in coumarin-30 using two-photon fluorescence and the Z-scan technique

The nonlinear propagation dynamics of 45 fs laser pulses in methanol solution has been studied with the two-photon fluorescence and the Z-scan technique. The competing nonlinear processes include self-focusing, self-phase modulation, filamention, intensity clamping and the two- photon absorption [1]. A systematic study has been performed of these nonlinear effects at different the laser powers. The simultaneous measurements of two-photon fluorescence and the transmission, displaying also continuum generation, were performed, to better understand the interplay between these effects [2]. In addition, the influence of a linear chirp of the laser pulse on the nonlinear propagation dynamics was investigated. \\[0pt] [1] H. Schroeder, S. L. Chin, Opt. Communications, 11, 1695-1703 (2002) \\[0pt] [2] M. C. Fischer, H. C. Liu, I. R. Piletic, and W. S. Warren, Opt. Express, 16, 4192-4205 (2008)