COMPACT 10 MW ALL-SOLID-STATE 491 NM LASER-BASED ON FREQUENCY-DOUBLING A MASTER OSCILLATOR POWER-AMPLIFIER LASER-DIODE

We report on continuous-wave blue-green light generation by direct fre quency doubling a monolithically integrated master oscillator power am plifier laser diode in a potassium niobate (KNbO3) crystal. 10 mW of d iffraction limited (M(2) less than or equal to 1.1) second-harmonic li ght at 491 nm is generated with a fundamental power of 760 mW incident on a 17 mm long crystal. The blue-green laser radiation is 100% polar ised and single-longitudinal mode with a frequency linewidth of simila r to 33 GHz corresponding to a coherence length of similar to 6 mm. Th e root-mean-square fluctuations of the second-harmonic output power is as low as O.1% and the power drift is less than 3% over six hours.