Optical and lasing characteristics of microporous quartz glass impregnated with a dye-activated epoxy polymer

A new solid-state active medium in the form of microporous quartz glass dye-doped by a coloured epoxy polymer was developed for dye lasers. The specific nature of the structure of this medium ensured improved mechano-physical and thermooptical characteristics combining the good optophysical properties of glasses with a long service life of dye-activated polymers. The rate of change of the refractive index with temperature, dn/dT = -7.5×10^-6 K^-1, was considerably less than that for the polymers used at present and also less than that for many optical glasses and crystals. Excitation, with YAG : Nd³⁺ laser radiation in a nonselective resonator, of this glass impregnated with an epoxy polymer activated with rhodamine C gave rise to stimulated emission in the spectral range 610–640 nm, and the efficiency of such emission was ~20%. In a distributed-feedback laser the tuning range was 607–665 nm and the width of the spectral line was 0.03 nm. The service life was ~10⁴ shots, which matched the best dye-doped solid-state matrices under these conditions.