Samarium 3+ -doped glass laser operating at 651 nm

Laser emission has been observed in a samarium3+-doped silica optical fibre in a Fabry-Perot-type laser cavity. The emission is centred on 651 nm and corresponds to stimulated transitions from the 4G5/2 level to the 6H9/2 level. The fluorescence and absorption associated with the metastable level are seen to be unusually narrow (3nm FWHM) for a trivalent rare earth in a disordered glass structure. The laser has operated in CW and Q-switched modes when pumped with 488 nm light at room temperature.