Features of three red laser dyes and effect on them the adjacency of their molecules

Abstract

We have developed and explored laser media on the basis of preliminary annealed xerogel SiO2 matrices doped with three laser dyes for 600 – 700 nm range of tuning that used actively in biomedical diagnostics and sensory analysis. Spectral, fluorescence, and laser characteristics of the dyes in solutions and matrices have been measured and analyzed. The influence of bulky fragments that may swing within structure of the dye molecule and its nearest adjacency on nonradiative losses in the excited S 1 state of this molecule have been revealed. The specific output laser energy of two laser dyes have appreciably increased in the matrix as compared with their methanol solution. The studied matrices have lasing in a nonselective cavity with red shift relatively the fluorescence maximum by value of 900 – 1700 cm -1 that may extend the penetration depth of laser biosensors radiation into organic tissues