基于全光纤萨格纳克干涉仪的温度不敏感磁场测量

Temperature-insensitive magnetic-field measurement using all-fiber Sagnac interferometers

研究了双折射磁光光纤萨格纳克(Sagnac)干涉仪透射谱的磁场和温度敏感性.实验表明,干涉仪透射谱会随着温度的增加向短波长移动(温度系数为0.435nm/C),其波长依赖性则随着磁场的增加而降低.据此,通过调节干涉仪内偏振控制器状态实现了温度不敏感的磁场测量,磁场系数为189mW/T2,实验结果与理论分析一致.

Magnetic field and temperature dependence of Sagnac interferometers consisting of birefringent magneto-optic fibers is inves- tigated. Experimental results show that the transmission spectrum of the all-fiber Sagnac interferometer moves towards the shorter wavelength side with the increase in temperature （temperature coefficient -0.435 nm/℃）, and the transmissivity becomes wavelengthinsensitive for a larger magnetic induction. And then, the temperature-insensitive magnetic field measurement is achieved by adjusting the polarization controller within the interferometer, and the magnetic field coefficient is 189 mW/T2 in the experiment, which is in agreement with the theoretical results.