Design of one-dimensional composite photonic crystal with high infrared reflectivity and low microwave reflectivity

In this paper, we proposed a one-dimensional (1D) composite photonic crystal (CPC) with high infrared reflectivity and low microwave reflectivity. Based on λ/4 photonic band gap theory and impedance matching principle, the unit cell structure of CPC was determined. The effects of material parameters, incident angle, the number of unit cell and reference wavelength on the forbidden band of infrared and pass band of microwave were analyzed. A 1D CPC composed of three photonic crystals with 27 layers was designed. Its average infrared reflectivity in the range of 3-5 μm reached 99.40%, and its average microwave reflectivity in the range of 14-16 GHz was only 0.16%. This CPC has good potential application in infrared/microwave compatible stealth.