Low threshold and compact cw Nd:YVO_(4)self-Raman lasers at 1176 nm and sum-frequency mixing of fundamental and first-Stokes wavelengths are demonstrated.A 20-mm Nd:YVO_(4)crystal is adopted in a compact plane-concave resonator.The results show that the cw Raman conversion is sensitive to cavity length.At an incident pump power of 22.5 W,output power of 1.53 W at 1175.6 nm is achieved,corresponding to the threshold of only 0.8 W and the slop efficiency of 8.1%.Intra-cavity sum-frequency generation is realized in a type-Ⅱphase-matching cut KTP crystal,480 m W at 558.6 nm is obtained at incident pump power of 12 W.
报道了基于非临界相位匹配磷酸钛氧铷晶体(RTP)的光参量振荡激光性能研究。采用激光二极管端面抽运Nd:YAP激光晶体,组成内腔式RTP-OPO系统,对比了在不同声光调Q重复频率下的信号光输出特性。在20 k Hz重复频率和13.1 W的抽运入射功率下,获得平均功率1.1 W的1.65μm人眼安全激光的输出,光-光转化效率为8.4%;在重复频率为5 k Hz时,获得了最窄脉4.4 ns,最高单脉冲峰值功率30.8 k W。结果表明,基于RTP晶体的OPO变频是获得1.6μm波段激光的一种有效新途径。