波长可切换窄线宽单频掺镱光纤激光器（特邀）

基于光纤环形激光器，设计出由三端口环形器、偏振控制器、未泵浦保偏掺镱光纤和光纤布拉格光栅组成的滤波器件作为高精度滤波器对谐振腔内的模式个数进行抑制，通过调谐偏振控制器，在保偏掺镱光纤内形成的梳状光谱和动态光栅，实现了窄线宽、单、双波长可切换单频掺镱光纤激光器。单波长运行时，在1064.37 nm处测得激光器输出线宽346 Hz，光信噪比大于50 dB，30 min内该激光器波长及功率的不稳定性均在0.01 nm和0.2 dB范围内。通过调节偏振控制器，单波长和双波长可以实现互相切换，双波长分别位于1064.156 nm和1065.236 nm。该技术为超窄线宽激光器的双波长输出提供了新的途径。

Wavelength switchable and tunable single-frequency narrow linewidth ytterbium doped fiber laser (Invited)

Based on fiber ring lasers, we designed a single-wavelength and dual-wavelength switchable single-frequency ytterbium-doped fiber laser. A high-finesse filter was composed of a three-port circulator, an unpumped ytterbium-doped fiber and a fiber Bragg grating, which was used to suppress the number of modes in the resonator. By tuning polarization controller, comb spectra and dynamic gratings were formed within Polarization Maintaining Ytterbium Doped Fiber(PM-YDF) and realized the output of a single-frequency fiber laser with narrow linewidth. The output linewidth of the laser was 346 Hz at 1064.37 nm, and the optical signal-to-noise ratio was greater than 50 dB. The instability of wavelength and power was within 0.01 nm and 0.2 dB in 30 min. By adjusting the polarization controller, the single and dual wavelengths could be switched to each other, and the dual wavelengths were located at 1064.156 nm and 1065.236 nm, respectively. This technology provides a new way for dual wavelength output of ultra-narrow linewidth lasers.