高质量CdSe单晶生长及其OPO性能研究

Growth and Optical Parametric Oscillator Properties of High Quality CdSe Single Crystal

本文利用有籽晶的HPVGF法生长了尺寸为∅54 mm×25 mm的高质量CdSe单晶,晶体为纤锌矿结构,(002)和(110)面的XRD摇摆曲线半高宽分别为54.4″和45.6″。使用红外显微镜和扫描电镜-能谱分析仪对晶体内部的夹杂相进行测试,表明晶体内部存在小尺寸富Se夹杂相。CdSe晶片在2.5~20μm范围内的透过率高于68%,平均吸收系数为0.037 cm^-1。制备出尺寸为10 mm×12 mm×50 mm且满足第Ⅱ类相位匹配条件的CdSe晶柱,在重频1 kHz,波长2.09μm的Ho∶YAG调Q泵浦源激励下,实现了中心波长为11.47μm,线宽为33.2 nm的激光输出,最大输出功率为389 mW。

High quality CdSe single crystal,with the sizes of 54 mm in diameter and 25 mm in length,was successfully grown by a high pressure vertical gradient freeze(HPVGF)technique using seed.The full width at half maximum(FWHM)of(002)and(110)X-ray rocking curves of the CdSe crystal with wurtzite structure are 54.4 arcsec and 45.6 arcsec respectively.The results show that there are some small-size Se inclusions in CdSe crystal by the test of infrared microscope and SEM-EDS.The transmission spectra show that the infrared transmission is above 68%and the mean absorption coefficient is 0.037 cm^-1 in the range of 2.5-20μm.Using fabricated type II CdSe crystal with the dimensions of 10 mm×12 mm×50 mm,we demonstrated an optical parametric oscillator(OPO)pumped by a 2.09μm acoustooptic Q-switched Ho∶YAG laser at a pulse repetition frequency of 1 kHz.Up to 389 mW output is obtained at the idler wavelength of 11.47μm with a linewidth of 33.2 nm.