【摘要】 利用耦合模理论对光纤熔锥声光器件进行了数值模拟,得到了全光纤声光衰减器传输谱和可调谐性。分析了带宽与声波长、耦合长度的关系。数值分析结果表明,声波在光纤熔锥中引起的轴向电介质微扰、耦合长度和工作波长都会对器件的传输谱产生影响,选择合适的设计参数可以制作较为理想的声光衰减器。实验上获得了损耗小于0.2dB,带宽大于200nm,动态范围为20dB的单模光纤熔锥可变衰减器,所得结果与理论分析相符合。这种器件可用于光纤通信及光纤传感。更多还原

【Abstract】 The performance of an acousto-optic variable attenuator based on single mode optical biconical fiber fused taper is analyzed by the coupled mode theory, and the spectrum, mode conversion efficiency, bandwidth and wavelength tuning range of Variable Optical Attenuator (VOA) are simulated numerically. The computed results show that the disturbance by the flexural acoustic wave in the fused fiber, the length of the device, and the performance wavelength of the device can affect the transmission spectrum of all-fiber acousto-optic variable attenuator. A fiber VOA with less than 0.2dB insertion loss, more than 200nm bandwidth and 20dB dynamic range is realized experimentally, and the results agree with the numerical theory. The devices with low loss and all-fiber are useful for telecommunication and sensing applications.更多还原