量子保密通信中光纤光栅的波长稳定性研究

为了改善量子保密通信设备中所用光纤布拉格光栅的长期波长稳定性,从工艺角度提出了采用特殊光纤涂覆层材料对常规的光纤光栅加以改进,并制作了基于新工艺的双金属温度补偿光纤光栅样品.理论研究了温度和应力等因素对光纤光栅中心波长的影响,分析了光纤光栅温度补偿的原理和方法.通过高温加速老化的方法,监测了所制作的新工艺光纤光栅样品在等效3年时间内中心波长变化情况,同时对比测试了原有工艺的部分样品.分析了所制作的光纤光栅在特定传输距离时应用于量子保密通信中的滤波特性.结果表明,新工艺的光纤光栅在3年等效老化时间内,中心波长漂移量均在产品允许的最大漂移范围内,较常规的光纤光栅工艺有较大改善,满足设备长期运行时对波长漂移精度的使用要求.

Research for wavelength stability of fiber Bragg grating in quantum secure communication

In order to improve the long-term wavelength stability of the fiber Bragg grating used in quantum secure communication, it is proposed to use special fiber coating material to improve the conventional fiber grating from fabrication process. Several bimetallic temperature compensated fiber grating based on the new process was also made. The influence of temperature and stress on the center wavelength of fiber grating was studied and the principle and method of fiber grating temperature compensation were analyzed theoretically. By means of accelerated aging at high temperature, the change of central wavelength of fiber Bragg grating based on new process within 3 years was monitored. At the same time, some samples of the original process were compared and tested. Finally, the filtering characteristics of the fabricated fiber grating applied to quantum secure communication at a specific transmission distance were analyzed. The results show that the central wavelength drift of fiber grating based on new process is within the maximum allowable drift value of the equipment within 3 years equivalent aging time. Compared with the conventional fiber grating process, it is greatly improved. The fiber Bragg grating based on the new process can meet the requirement of wavelength drift accuracy in the long run of the equipment.