SOLID-STATE DYE-LASERS BASED ON MODIFIED RHODAMINE 6G DYES COPOLYMERIZED WITH METHACRYLIC MONOMERS

Modified rhodamine 6G molecules with polymerizable double bonds have b een copolymerized with methacrylic monomers and the resulting polymers have been pumped at 337 nm with a N-2 laser in a transversal configur ation. The preparation of these new materials is described in detail a nd their lasing properties are evaluated. Important increases in photo stability, with lasing efficiencies similar to those found for the par ent dye rhodamine 6G in ethanol solution, have been obtained for some of these materials. Lifetimes (measured as an 80% efficiency drop) in excess of 20 000 shots at repetition rates of 2 Hz have been demonstra ted. Strong dependence on pump repetition rate was observed. Possible mechanisms and processes responsible for the behavior of these materia ls are discussed. By using a rotating system where the sample is scann ed in a continuous way, the laser output remained stable, with no sign of degradation, after 500 000 shots. (C) 1996 American Institute of P hysics.