提出了一种低噪声、线宽小于4 kHz、波长为1 083 nm的线形腔单频光纤激光器.该激光器引入了偏振控制器来消除线形腔内的空间烧孔效应, 从而抑制了多纵模振荡.实验结果表明：泵浦功率在40～200 mW范围内时, 可获得稳定的单纵模振荡, 且最大输出功率可达46 mW, 光学信噪比大于60 dB, 其光光转换效率和斜率效率分别为23%和33.3%；经过1 h的观察, 测得的激光输出功率以及光谱不稳定性分别小于3%和0.9%；在整个观察期内, 没有出现模式跳跃和模式竞争现象.

A low noise single-frequency 1 083 nm fiber laser with a linear cavity was presented and demonstrated with a linewidth of 4 kHz. A polarization controller was introduced to eliminate the spatial hole burning effect in the linear cavity to suppress the multiple longitudinal mode oscillation. The results show that, when the pump power is in the range of 40 mW～200 mW, the single-frequency oscillation is very stable, the maximum output power can reach to 46 mW, the optical signal to noise ratio is larger than 60 dB, the maximum optical-to-optical conversion efficiency and the slope efficiency is 23% and 33.3%, respectively. The stable single-frequency operation can be maintained more than 1 hour with the instability of the output power and the spectrum fluctuations less than ±3% and 0.9% respectively. There are no mode hopping and mode competition during the entire observation.