We report a pulsed Raman laser at 1193 nm based on synthetic diamond crystals with a record output power of 24.5 W and a slope efficiency of 57%. We compared the performance of an anti-reflection coated crystal at normal incidence with a Brewster cut sample. Raman oscillation was achieved at both room temperature and under cryogenic operation at 77 K. Modeling of these experiments allowed us to confirm the value of Raman gain coefficient of diamond, which was found to be 13.5 ± 2.0 cm/GW for a pump wavelength of 1030 nm.

Recent developments in high-finesse cavities now make broadly tunable, continuous-wave Raman lasers possible. The design and preliminary characterization of what is to the authors' knowledge the first continuous-wave Raman laser in H(2) are presented. The threshold is currently at 2 mW of pump, making diode laser pumping possible. The maximum photon conversion efficiency observed was 35% at 7.6 mW of pump power.

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Using a 14-mm thick volume Bragg grating, spectral bandwidth of a cw-operated diode laser array is narrowed to 7 GHz (FWHM). Total output power reaches 13.5 W cw, of which 86% is in the 7-GHz band. With such a narrow bandwidth, it is possible to temperature tune laser frequency across O(2) X(3)Pi --> b(1)Sigma(+) absorption line at 763.8 nm, efficiently generating O(2)((1)Delta) molecules.

By frequency-stabilizing the output from an Erbium fiber amplifier at 1580 nm to a high-finesse cavity (finesse ~6300) formed by two high-reflectance, low-loss, concave mirrors, we achieve 22.4+/-2.0 kW intracavity circulating power and 101+/-9 MW/cm(2) cw intracavity intensities on the surfaces of the mirrors. Repeated experiments show no damage to the mirrors' coating. In addition, small variations of the mirrors' radius of curvature are observed and measured by recording the cavity's transverse-mode range. The mirrors' 10 cm radius of curvature changes as function of laser intensity at a rate of 105 mum/(MW/cm(2)).