Influence of a small inhomogeneous broadening of Cr3+:LiSrAlF6 emission line on the laser performance

Experimental investigations of Cr:LiSAF laser output spectra have shown that its emission line is inhomogeneously broadened. This is clearly evident from the fact that the measured laser line width is always much broader than what is possible due to 'spatial hole burning' in a Cr:LiSAF standing-wave resonator, if the Cr:LiSAF emission line is assumed to be homogeneously broadened. By assuming the possibility of a slight inhomogeneous broadening of the Cr:LiSAF emission line, corresponding to the T-4(2)-(4)A(2) transition of Cr3+-ions, the observed laser line width can be explained. We have calculated the extent of laser output reduction due to inhomogeneous broadening, by means of a simple model. By comparing the measured laser output energy with the calculated laser output, the relative spectral inhomogeneity parameter beta is estimated to be beta = 1.6-1.8. (C) 2001 Elsevier Science Ltd. All rights reserved.