用于碱金属蒸汽激光器泵浦的窄线宽780 nm半导体激光源

780 nm Diode Laser Source with Narrow Linewidth for Alkali Metal Vapor Laser Pumping

780.0nm窄线宽、高功率半导体激光器对于发展Rb碱金属蒸汽激光器具有重要意义 为获得好的泵 浦效果 泵浦光谱与碱金属蒸汽的吸收光谱需严格匹配 必须压窄半导体激光输出线宽 且稳定中心波长 反射式体布拉格光栅(RVBG)外腔反馈是目前实现窄光谱光源的主要方案之一 本文提出了快轴准直镜 光 束变换器 慢轴准直镜 反射式体布拉格光栅(FAC BTS SAC RVBG)的结构 压缩入射到 RVBG 的激光发散 角 提高RVBG有效反馈率 相对于常规的“FAC+SAC+RVBG”结构 提升光谱锁定效果 基于“ FAC+BTS+ SAC+RVBG”结构 研制出780nm窄线宽激光器 连续功率达到47.2W 通过对RVBG精确温控 可将中心 波长稳定在780.00nm 采用单模光纤探测 光谱宽度为0.064nm(FWHM) 温漂系数为0.0012nm/℃ 电 流漂移系数为0.0013nm/A 可用于Rb碱金属蒸汽激光器泵浦.

The 780.0 nm narrow linewidth and high power diode laser is of great significance for the development of Rb alkali metal vapor laser.In order to obtain good pumping effect,the absorption spectra of the pump spectrum and the alkali metal vapor must be strictly matched,the output line width of the diode laser must be narrowed,and the central wavelength must be stabilized.External cavity feedback of reflective volume Bragg grating(RVBG)is one of the main schemes to realize narrow spectrum light source at present.The structure of fast axis collimating mirror,beam convertor,slow axis collimating mirror,reflection type body Bragg grating(FAC-BTS-SAC-RVBG)is proposed.The laser divergence angle of incident to RVBG is compressed to improve the effective response rate of RVBG.Compared with the conventional“FAC+SAC+RVBG”structure,the spectral locking effect is improved.Based on the FAC-BTS-SAC-RVBG structure,a narrow linewidth laser at 780 nm was developed,with a continuous power of 50 W.By controlling RVBG temperature,the central wavelength could be stabilized at 780.00 nm.Using single mode optical fiber probe,spectral width is 0.064 nm(FWHM),temperature drift coefficient is 0.001 2 nm/℃,current drift coefficient is 0.001 3 nm/A.The structure can be used for Rb alkali metal vapor laser pump.