Tunable solid-state lasers incorporating dye-doped, polymer– nanoparticle gain media

Tunable laser action in the visible spectrum has been established for what is believed to be the first time by use of dye-doped, polymer–silica nanoparticle gain media. The silica nanoparticles, ranging from 9 to 12 nm in diameter, appear to be uniformly dispersed in the poly(methyl methacrylate) matrix because the optical homogeneity of the gain medium is maintained. With Rhodamine 6G dye and 30% weight-by-weight silica nanoparticles, laser action was established in the 567–603-nm range. At the peak wavelength $\left(\lambda \approx 580 \mathrm{nm}\right)$, laser conversion efficiency is $\sim 63\%$ at a beam divergence of $1.9 \mathrm{mrad}$ ($\sim 1.3$ times the diffraction limit). The new solid-state gain medium also exhibits a reduction in $\left|\partial n/\partial T\right|$.