NEWLY SYNTHESIZED DYES AND THEIR POLYMER GLASS COMPOSITES FOR ONE-PHOTON AND 2-PHOTON PUMPED SOLID-STATE CAVITY LASING/

A newly synthesized laser dye, l-N-(hydroxyethyl)amino)styryl]-N-methy lpyridinium tetraphenylborate (ASPT or dye I) has high thermal stabili ty and photostability. To modify the solubility of dye I, a series of dyes has been synthesized. Using dye I doped polymer film with a refra ctive index less than that of the glass substrate, a leaky waveguide d evice has been investigated. Under pump conditions of 532 nm wavelengt h, 10 ns pulse width, and 5 Hz repetition rate, one-photon cavity lasi ng was obtained at 590 nm, with a lasing efficiency of 12%, and lasing lifetime >3 x 10(4) pulses. Utilizing dye I doped bulk polymer rods, two-photon pumped frequency up-converted cavity lasing has also been a ccomplished using a Q-switched Nd:YAG laser as the pump source. The ne w dyes possess a much greater two-photon-absorption cross section and much stronger up-converted fluorescence emission than that exhibited b y common organic dyes (such as rhodamine). The cavity lasing wavelengt h and pulse duration were 600 nm and 3-6 ns obtained with a pump wavel ength of 1.06 mu m and pump pulses of 10 ns. Lasing lifetime, in terms of pulse numbers, was more than 4 x 10(4) pulses at 2 Hz repetition r ate. By impregnating these dyes into a sol-gel glass:poly(methyl metha crylate) (PMMA) and Vycor glass:PMMA composite glasses, two-photon pum ped cavity lasing properties have also been studied.