Spectroscopy and laser operation of Sm(3+)-doped lithium lutetium tetrafluoride (LiLuF(4)) and strontium hexaaluminate (SrAl(12)O(19)).

We report on laser operation in the orange and red spectral range in samarium (Sm(3+))-doped fluoride and oxide crystals at 300 K. Sm(3+)-doped LiLuF(4) (LLF) and SrAl(12)O(19) (SRA) crystals were grown by the Czochralski-technique and utilized for spectroscopic investigations and laser experiments. The spin-forbidden transitions of Sm(3+)exhibit low cross sections the order of 10(-21) cm(2), but high radiative upper state lifetimes of several ms in both crystal systems. Under 2ω-OPSL-pumping at 480 nm, orange laser operation was achieved with Sm:LLF and Sm,Mg:SRA at lasing wavelengths of 606 nm and 593 nm, respectively. Furthermore laser oscillation was demonstrated at 648 nm in the red and 703 nm in the deep red spectral range with Sm:LLF and Sm,Mg:SRA, respectively. Output power levels of several 10 mW were obtained at slope efficiencies of up to 15 %. Most of the realized lasers were operating in a strongly modulated or even self-pulsing regime.