High-Precision Tunable Single-Frequency Fiber Laser at 1.5 μm Based on Self-Injection Locking

作者：Huang, Linhuan; Guan, Zhe; Yang, Changsheng^*; Tan, Tianyi; Zhao, Qilai; Lin, Wei; Zhou, Kaijun; Xu, Shanhui; Yang, Zhongmin

来源：IEEE Photonics Technology Letters, 2022, 34(12): 633-636.

DOI：10.1109/LPT.2021.3090947

• High-precision wavelength tunability
• single-frequency fiber laser
• self-injection locking

A high-precision tunable single-frequency fiber laser (T-SFFL) at 1.5 mu m based on self-injection locking is experimentally demonstrated. By virtue of an effective filtering and self-injection locking scheme, a stable single-longitudinal-mode operation of the fiber laser is obtained. The fine wavelength tunability is implemented by stretching a uniform fiber Bragg grating in the self-injection loop, and the laser wavelength is tuned from 1550.28 to 1560.40 nm with a tuning accuracy of less than 54 pm. In the whole tuning range of 10.12 nm, an output power of approximately 5 mW and an optical signal-to-noise ratio of 71 dB are synchronously obtained with this laser system. Additionally, the measured laser linewidth is less than 630 Hz and the relative intensity noise is lower than -149 dB/Hz at frequencies from 0.4 to 7.5 MHz. It is believed that this 1.5 mu m high-precision T-SFFL, can he a promising candidate for the optical communications system applications.