CHROMIUM-DOPED FORSTERITE RING LASER

Operation of a Cr4+:Mg2SiO4 crystal in a ring cavity is studied with d ifferent dopant levels. Threshold energies of 13 mJ, 10.6 mJ and 11 mJ were measured for Mitsui low-doped, Russian and Mitsui highly doped c rystals respectively, Slope efficiencies of 0.9%, 1.1% have been obtai ned for the Mitsui low-doped and Russian crystals, An efficiency of 3. 6% was recorded for the highly doped chromium forsterite crystal from Mitsui. The peak output wavelength is 1275 nm. These results are compa red with these crystals in the simple cavity.