1.8W，高效率，泵浦增强，3.8µm 窄线宽光参量振荡器。

1.8 W, high efficiency, pump-enhanced, narrow linewidth optical parametric oscillator at 3.8 µm.

出版信息

Opt Express. 2023 Mar 27;31(7):11156-11163. doi: 10.1364/OE.486794.

Abstract

A high efficiency, continuous-wave, narrow linewidth, pump-enhanced optical parametric oscillator (OPO) at 3.8 µm was demonstrated, which was pumped by a 1064 nm fiber laser with a linewidth of 18 kHz. The low frequency modulation locking technique was employed to stabilize the output power. The wavelengths of signal and idler were 1475.5 nm and 3819.9 nm at 25 °C, respectively. The pump-enhanced structure was applied, leading to a maximum quantum efficiency of over 60% with pump power of 3 W. The maximum output power of idler light is 1.8 W with a linewidth of 363 kHz. The excellent tuning performance of the OPO was also demonstrated. In order to avoid mode-splitting and decrease of pump enhancing factor due to feedback light in the cavity, the crystal was placed obliquely to the pump beam and the maximum output power was increased by 19%. At the maximum output power of idler light, the M factors in the x and y directions were 1.30 and 1.33, respectively.

摘要

一种高效率、连续波、窄线宽、抽运增强的 3.8μm 光学参量振荡器（OPO）得到了演示，它由线宽为 18kHz 的 1064nm 光纤激光器抽运。采用低频调制锁定技术稳定输出功率。在 25°C 时，信号和闲频光的波长分别为 1475.5nm 和 3819.9nm。采用抽运增强结构，在 3W 的泵浦功率下，量子效率超过 60%。闲频光的最大输出功率为 1.8W，线宽为 363kHz。该 OPO 还表现出了优异的调谐性能。为了避免由于腔内反馈光导致的模式分裂和抽运增强因子的降低，将晶体倾斜放置于泵浦光束，从而将最大输出功率提高了 19%。在闲频光的最大输出功率下，x 方向和 y 方向的 M 因子分别为 1.30 和 1.33。