Lasing properties of near-infrared laser dyes in the liquid and solid state

摘要

The photophysical and lasing properties of a number of near infrared laser dyes from different dye classes - extended rhodamines, oxazines, cyanine and styryl dyes - predominantly in liquids but also in poly(methyl methacrylate) (PMMA) based hosts are reported in this paper. The different dyes have been found to exhibit fluorescence quantum efficiencies in the range of 0.01-0.88 in solution. The fluorescence efficiency for a number of the dyes has been found to be heavily dependent on the solvent characteristics. Laser slope efficiencies in the range of 20-66% have been recorded for the dyes under nanosecond laser pumping at or close to the wavelength of their absorption maximum. The lasing wavelengths of the samples were found to range from 647 nm to 815 nm. Some differences in the lasing efficiency has been noted between the behaviour of the liquid and solid-state dye samples, in particular for the dye Oxazine 1. A number of the dye/solvent combinations have been further tested in a flashlamp pumped dye laser apparatus with success, with moderate laser efficiency at lasing wavelengths ranging from 692 to 824 nm having been achieved.