Dye-doped, polymer-nanoparticle gain media for tunable solid-state lasers

Tunable laser action, in the visible spectrum, has been established using dye-doped, polymer-silica nanoparticle gain media. The silica nanoparticles, averaging about 12 nm in diameter, appear to be uniformly dispersed in the polymethyl methacrylate (PMMA) matrix, since the optical homogeneity of the gain medium is maintained. Using rhodamine 6G dye and 30% weight-by-weight (w/w) silica nanoparticles, laser action was established in the 567-603 nm range. At the peak wavelength (lambda similar to 580 nm) laser conversion efficiency is similar to63% at a beam divergence of 1.9 mrad (similar to1.3 times the diffraction limit). The new solid-state nanocomposite gain media also exhibits a reduction in \partial derivativen/partial derivativeT\ because the thermo-optic coefficient of silica is opposite in sign to that of the PMMA polymer-host component.