为了实现新波长、高效率的激光输出,建立了外腔型拉曼实验装置并对YVO4晶体进行了测量。采用提拉法生长了最大尺寸为28 mm×40 mm,质量为126 g的高光学质量YVO4晶体,以脉冲宽度为40 ps的Nd:YAG锁模激光器作为激发源,研究了YVO4晶体的外腔拉曼输出特性。结果显示,该激光器多波长输出的总转换效率达到51.4%,最大输出能量为2.21 mJ;1 175 nm一级斯托克斯拉曼输出的最高转换效率为32%,最大输出能量为0.57 mJ;1 313 nm二级斯托克斯拉曼输出的最高转换效率为12.3%,最大输出能量为0.36 mJ。结果表明,采用外腔型结构可使YVO4晶体的拉曼输出性能显著提高。

In order to obtain new wavelengths and high efficient laser outputs,an external resonator Raman experimental setup was established and the properties of YVO4 crystals were measured. Then,a high optical quality YVO4 crystal with the largest size of 28 mm×40 mm and a mass of 126 g was grown by Czochralski pulling method.The Raman output properties of YVO4 crystals in the external resonator were researched using a mode-locked Nd:YAG laser with a pulse width of 40 ps as the pump source.The results indicate that the total conversion efficiency for multi-wavelength output has reached 51.4%,and the largest output energy is 2.21 mJ. Moreover,the highest conversion efficiency for the first Stocks Raman output at 1 175 nm is 32%,and the largest output energy is 0.57 mJ. The conversion efficiency for the second Stocks Raman output at 1 313 nm is 12.3%,and the largest output energy is 0.36 mJ. These results reported here show that the external resonator structure can improve the Raman performance of YVO4 crystals evidently.