基于一维光子晶体的波长调制的光学传感系统研究

Research on Wavelength Modulation Optical Sensor Systems Based on One Dimensional Photonic Crystal

本文设计了一种基于纳米尺度分布式布拉格反射光栅(nano-DBR)结构的一维光子晶体宽禁带波长调制系统。根据1.55μm通信光所在波段性质,DBR被精确的设计成光子带隙材料,由硅/空气多层结构周期性重复组成。其中,可动DBR受外力作用发生位移,利用间距的变化调制光子晶体透射谱的变化。采用严格耦合波分析(RCWA)来计算6个周期带隙结构的峰值透射谱变化。通过对模拟数据的统计分析,可得出所设计的nano-DBR一维光子晶体系统,在对应两个DBR间距位移变化从0到1μm时,对应的一级透射峰可调制的范围在1.55μm^2.7μm,峰值最低透射率为0.8366。该系统灵敏度可达1.2~1.3左右。与同类型波长调制传感系统比较,在理论上具有更宽带隙调制范围,高辨识度和高灵敏度的优势。

In this paper,a one-dimensional photonic crystal wide band gap wavelength modulation system based on nanoscale distributed Bragg reflection grating(nano-DBR)has designed.DBR was accurately designed as a photonic band gap material consisting of a silicon/air multilayer structure that repeated periodically according to the properties of the 1.55μm communication light band.Among them,the movable DBR was displaced by the external force,and the change in the transmission spectrum of photonic crystals was modulated by the change in the distance.Rigorous coupled wave analysis(RCWA)was used to calculate the peak transmission spectrum changes of six periodic bandgap structures.Through statistical analysis of the simulated data,it was obtained that the proposed nano-DBR one-dimensional photonic crystal system can modulate a range of 1.55μm^2.7μm transmission peak and a peak minimum transmittance of 0.8366 when the displacement change of two DBR spacing ranges from 0 to 1μm.The sensitivity of the system can be up to about 1.2~1.3.Compared with the same type of wavelength modulation sensing system,it has more wideband gap modulation range in theory,and can be compatible with more signal detection areas,and has the advantages of high identification and high sensitivity.