基于电光聚合物缺陷光子晶体的脉冲电场测量技术

Photonic Crystal with Electro-optic Polymer Defect for a Pulse Electric Field Sensor

针对幅值强、频带宽、持续时间短等脉冲电场测量需求,本文提出一种基于电光聚合物缺陷光子晶体的全介质脉冲电场传感器.在周期性分布的光子晶体中引入电光聚合物作为缺陷层,外界电场的作用下,电光聚合物的折射率发生改变,这将会引起光子晶体的谐振频率偏移,监测谐振频率的变化即可实现被测电场测量.本文通过理论分析与数值模拟光入射角度不同且入射波的偏振状态不同时,光子晶体的结构参数对光子晶体传输光谱特征的影响规律,验证了该传感器的电场敏感特性.仿真结果表明,通过合理设计传感器的结构参数,结合波长-光强解调系统,基于电光聚合物缺陷光子晶体的电场传感器的电场分辨力可以达到约30V/m,最高可测量场强则可达到兆V/m量级.

As for the measurement requirements of the pulse electric field with high intensity,wide frequency band and short duration,an all-dielectric electric field sensor based on photonic crystal with electro-optic polymer defect was proposed in this paper.The electro-optic polymer in the form of a defect layer was inserted in the periodic one-dimensional photonic crystal structure.The variations of refractive index of electro-optic polymer under the externally applied electric fields may induce the changes of the resonance wavelength of the defect mode.Accordingly,the applied electric field may be measured by monitoring the shift of the resonant wavelength.It is theoretically shown that the minimal detectable electric field of30 V/m can be achieved and the maximum detectable field could reach up to the order of MV/m.