Polarization temporal dynamics in a dye microlaser

We have investigated the temporal dynamics of the output polarization of a dye microlaser operating in a transient regime, i.e., under femtosecond excitation. In these conditions the dipole angular diffusion has an important role in the formation of the microlaser pulse, as is shown in a theoretical model. By performing the experiment for different values of the microcavity length and varying the polarization angle, we measured threshold and buildup time of the microlaser and compared the results obtained with two dye solutions of different viscosity. The agreement between theory and experimental results is adequate. (C) 1996 Optical Society of America