Research On Permitted Parameter Of PPRTA And Yb:YAG Laser

Quasi-phase matching of optical frequency changes has a high nonlinearcoefficient,that we can make use it. It conforms the phase matching requirements in awide bandwidth, also has the advantage of high conversion efficiency, so attractedwidely attention and research. As the technology of the periodically poled crystals bythe electric field polarization improving, using of periodically poled crystal dosolid-state quasi-phase, to achieve of optical frequency conversion process and thequasi-phase optical parametric process are becoming research focus.This paper compared several common periodically poled crystals, we also did sometheoretical research for quasi-phase-matched frequency doubling process withperiodically poled the arsenate titanyl rubidium crystal（PPRTA）. In experiment, wecompleted of the laser output of Yb: YAG crystal all-solid-state lasers with LDend-pumped, and did some for exploration clamping. The main work is as follows:⑴According to quasi-phase matching expressions of the periodically poled crystalsof doubling frequency and Sellmeier equations, obtained the relationship betweenPPRTA crystal in type-I and-II base on band optical wavelength. By numericalsimulation, we studied the bandwidth of permitted parameters (permittedwavelengths, permitted temperature, permitted angle and permitted polarizedperiod) for PPRTA crystal in type-I and-II. We obtained the advantages of thepermitted parameter for type-II is greater than the permitted parameters for thetype-I. This provides a good theoretical support for PPRTA crystal of quasi-phasefrequency multiplication in type-II.⑵According to the cavity’s optical ABCD transformation matrix theory, wecalculated the cavity length of the metastable zone by numerical analysis method.In experiment, we researched and analyzed the all solid laser with LD pumped,achieved continuous laser output by Yb: YAG crystal in the concave cavity withLD pumped and V-shaped cavity. As for plane concave resonators withdual-wavelength output at1030nm and1050nm, achieved stable dual-wavelengthoutput after a larger number of experiments. We had tested the mode-locked usingSESAM replaced the plane mirror in V-shaped cavity, and estimated the criticalspot radius of SESAM mode-locked, and achieved a stable Q-switched output.