1 西北大学省部共建西部能源光子技术国家重点实验室，陕西 西安 710127
2 西北大学陕西省全固态激光及应用工程技术研究中心，陕西 西安 710127
3 西北大学光子学与光子技术研究所陕西省光电子技术重点实验室，陕西 西安 710127
展示了一种基于环形器的线形腔可控掺镱自扫光纤激光器，腔两端的反射光在掺镱光纤内形成驻波场，产生空间烧孔效应，进而诱导形成动态光栅，产生自扫效应。当泵浦功率达到22.5 mW时，获得了正向自扫效应，当泵浦功率为48.8 mW时，获得的最大自扫范围约为6 nm (1065.4217～1071.4225 nm)。在整个实验过程中，获得的扫描速度为0.56～8.83 nm/s，平均脉冲重复频率为12.08～115.20 kHz。当泵浦功率为161.3 mW时，获得的最大光学信噪比为53.18 dB。实验中，在环形器内引入一个机械式可调谐光衰减器，通过改变腔内损耗，简单有效地对自扫范围和自扫速度等自扫特性进行了调控，并将自扫范围扩大为10.83 nm。
激光器 光纤激光器 自扫效应 光谱特性 微秒脉冲 中国激光
2022, 49(23): 2301003
Author Affiliations
Abstract
1 State Key Laboratory of Photoelectric Technology and Functional Materials, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics & Photon-technology, Northwest University, Xi’an 710069, China
2 Shaanxi Engineering Technology Research Center for Solid State Lasers and Application, Provincial Key Laboratory of Photo-electronic Technology, Northwest University, Xi’an 710069, China
We reported a wavelength-flexible all-polarization-maintaining self-sweeping fiber laser based on the intracavity loss tuning brought by the bent optical fiber. The bidirectional cavity structure achieved the self-sweeping effect due to the appearance of the dynamic grating in the active fiber with the spatial hole burning effect. Under this, a section of fiber was bent into a circle for adjusting the loss of the cavity. With a descending diameter of bent fiber circle, the sweeping range moves to the shorter wavelength and covers a wide range from 1055.6 to 1034.6 nm eventually. Both the initial wavelength of self-sweeping regime and the threshold of the fiber laser show exponential correlation with the diameter of the circular fiber. Our work provides a compact and low-cost way to achieve the broad wavelength-flexible self-sweeping operation.
fiber laser self-sweeping effect bidirectional cavity flexible wavelength all-polarization maintaining Chinese Optics Letters
2021, 19(4): 041401
