Second Harmonic Generation Of High-power Coherent Beam At532nm

This paper reports the experimental results of the high-power stable coherent beam at532nm. The beam is used for the generation of the squeezed state light, the experimentrequires that power of the coherent beam is around300mW and the time stabilization isone hour or more.Squeezed state light is a nonclassical optical field which has extensive applications inhigh sensitivity optical measurement, sub-shot-noise-limit optical measurement andquantum information research.Based on the optical second harmonic generation and the function of the cavity whichcan improve the conversion efficiency of second harmonic generation, the author designsa frequency doubling system and the modules required in practical systems. Focusing onthe experimental scheme of the cavity, the article describes the fundamental principles ofsecond harmonic generation in the nonlinear optics and principles of the cavity, then theauthor designs the mechanical structure of the cavity, after that calculates the theoreticaloptimal parameters of cavity mirrors and the key optical parameters of mode matching.Discussing the factors that limit the conversion efficiency of the second harmonicgeneration, including the direction of the fundamental frequency and the stability of thepolarization, the working time of the electronics, the temperature of the crystal, etc. Aboveall, the author modifies the experimental scheme. Finally, by the locking technology whichHanch and Couillaud proposed in1989s, the preliminary results show that a long-playingand stable output power is300mW at the cave laboratory of Center for GravitationalExperiments of HUST, when the power of fundamental frequency beam is1W.