|
光子学报 2007
Optically Tunable Narrowband Filter Using Liquid Crystal Defect in 1-D Photonic Crystal
|
Abstract:
Based on the theory of liquid crystal continuum,the tuning principle of one dimensional Si/SiO2 photonic crystal embedded in a nematic liquid crystal as a defect layer is analyzed and the relationship between applied voltage and tuning range is studied numerically by using transmission matrix method.The structure parameters of a tunable filter with narrow bandwidth and broad tuning range are determined through simulation computation.The computation results show that the tuning range achieve 100.8 nm between 1 600.6 nm and 1 499.8 nm when the applied voltage varies from 0.955 V threshold to 5 V saturation.The obtained tuning range covers telecommunication C band and almost S and L band.FWHMs(full width at half maximum) of the transmission peaks are between 0.074 nm and 0.090 nm,and the differences of bandwidths less than 17.8 percent.