论文部分内容阅读
基于法拉第效应,正交双频光纤激光器已经被证明可用于实现磁场传感。但这种传感器对磁场的灵敏度与激光器初始的拍频频率相关。因此对这种传感器的磁场灵敏度与拍频频率的关系进行了研究。理论和实验结果表明,传感器对磁场的灵敏度与拍频频率间呈非线性关系,并且灵敏度随着拍频频率的减小而增大。该灵敏度存在一个由费尔德常数决定的上限值。对于实验中基于掺铒光纤制备的短腔光纤激光器,通过将初始拍频频率降至2 MHz,获得了激光器对磁场响应的最大灵敏度43 Hz/μT。此外,激光器初始拍频频率与抽运激光的偏振态也有关系。实验表明,通过调谐抽运激光的偏振态,可以动态地调谐传感器对磁场的灵敏度。
Based on the Faraday effect, orthogonal dual-frequency fiber lasers have proven to be useful for magnetic field sensing. However, the sensitivity of this sensor to the magnetic field is related to the initial beat frequency of the laser. Therefore, the relationship between the magnetic field sensitivity of this sensor and the beat frequency has been studied. Theoretical and experimental results show that the sensitivity of the sensor to the magnetic field has a nonlinear relationship with the beat frequency, and the sensitivity increases with the decrease of the beat frequency. This sensitivity has an upper limit determined by the Verdet constant. For experiments of short cavity fiber lasers based on erbium-doped fibers, the maximum sensitivity of the laser to the magnetic field response of 43 Hz / μT was obtained by reducing the initial beat frequency to 2 MHz. In addition, the laser’s initial beat frequency is also related to the pumped laser’s polarization state. Experiments show that by tuning the pumped laser polarization state, the sensitivity of the sensor to the magnetic field can be dynamically tuned.