LD抽运c-cut Nd:YVO₄/a-cut YVO₄/c-cut GdVO₄同步脉冲多波长拉曼激光器的研究

Study on Synchronously Pulsed Multi-Wavelength Diode-Pumped Raman Laser Based on c-cut Nd:YVO₄/a-cut YVO₄/c-cut GdVO₄

摘要: 本文报道了一种采用c-Nd:YVO₄为自拉曼晶体，a-YVO₄和c-GdVO₄作为拉曼晶体的声光调Q同步脉冲三波长复合拉曼激光器，利用c切YVO₄和c切GdVO₄都有的有效259 cm⁻¹次级频移，在腔内加入a切YVO₄提高1178 nm斯托克斯激光增益以实现高功率抽运下三种一阶斯托克斯光的增益相对平衡。采用声光调Q，实现了1097 nm、1177 nm、1178 nm三个频移对应的一阶斯托克斯光同步脉冲三波长高峰值功率输出，且无二阶斯托克斯光产生。当脉冲重复率为10 kHz，入射泵浦功率为6.42 W时，1097 nm，1177 nm和1178 nm三波长同步脉冲激光平均功率为885 mW，光–光转换效率为13.79%。

Abstract: This paper reports an actively Q-switched synchronous pulse three-wavelength composite Raman laser using a c-Nd:YVO₄ as the self-Raman crystal, an a-YVO₄ and a c-GdVO₄ as the Raman crystals. By utilizing the common effective secondary Raman shift of 259 cm⁻¹ in c-cut YVO₄ and c-cut GdVO₄, and the relative balance of gain among the three first-order Stokes lines under high-power pumping conditions is achieved by introducing an a-cut YVO₄ crystal into the cavity to enhance the 1178 nm Stokes laser gain. The use of acousto-optic Q-switching enables the simultaneous pulse output of the first-Stokes light at 1097 nm, 1177 nm, and 1178 nm, achieving high peak power. At a pulse repetition frequency of 10 kHz and an incident pump power of 6.42 W, the maximum effective output power of the combined laser at 1097 nm, 1177 nm, and 1178 nm is 885 mW, and the optical-to-optical conversion efficiency was 13.79%.