wavelength dependent time development of the intensity of dye solution lasers

It has been observed that the intensity of laser emission from two different dye solution lasers (DTTC in DMSO and cryptocyanine in glycerol) reaches a maximum at the shortest wavelength in the emission band before it peaks at the longest. A simple model of dye solution lasers which explains this wavelength-time effect is presented. This effect can be interpreted to yield information on the rate of relaxation of internal energy of the dye molecule. The evidence suggests that, on the time scale of the laser action in these experiments (∼20 ns) the ground state of the dye molecule is inhomogeneously broadened. In addition, it is shown that certain other of the dye laser's properties may be understood by analysis of the solution's absorption and fluorescence spectra.