1560nm连续光半导体激光器经PPLN倍频及经铷吸收光谱稳频

1560 nm CW Diode Laser Frequency Doubling by Using PPLN Crystal and Frequency Locking via Rubidium Absorption Spectroscopy

将激光器锁定到合适的参考频率上,可以有效地改变激光器的频率稳定性。1560 nm的分布反馈式半导体激光器,可以通过倍频锁定于铷原子吸收线上。实验中我们利用PPLN准位相匹配晶体进行倍频,当输入光为1.6 W时可以获得25 mW的倍频光,非线性转换系数为0.96%/W。我们还将激光器的频率锁定于Rb原子的吸收线上,30 s内剩余频率起伏约为±3.5 MHz。

Locking laser to a proper reference frequency can obviously improve the laser frequency stability. We can lock 1 560 nm distributed feedback （DFB） diode laser to Rubidium absorption line via second harmonic generation （SHG）. The second harmonic wave is produced by use of a PPLN crystal in our experiment. About 25 mW of output power at 780 nm is generated when input power of fundamental wave is 1.6 W, and the nonlinear conversion efficiency is 0.96 %/W. We stabilize the laser frequency on rubidium absorption spectroscopy, and the residual frequency fluctuation is ±3.5 MHz in 30 s.