随角异色光子晶体薄膜的制备与FDTD模拟

Preparation and FDTD simulation of photonic crystal thin films with angle-dependent structural color

具有随角异色性能特征的光子晶体正逐渐成为较好的光学防伪薄膜材料.采用时域有限差分(finite difference time domain,FDTD)法研究光子晶体的光调制特性,以空气柱形2维光子晶体为研究对象,通过光学仿真分别模拟了不同孔洞直径、孔洞间隙的2维光子晶体的反射光谱.结果发现,孔洞直径为800 nm、间隙为800 nm、深度为400 nm的2维光子晶体具有较好的随角异色特征.采用磁控溅射法进行了在Si衬底表面制备Cr-Si Ox双层膜结构的实验,并利用光刻法制备了相应的光子晶体,实验结果与模拟结果匹配.

Photonic crystals with angle-dependent structural color are developed as new optically variable ink for anti-counterfeiting.The finite difference time domain(FDTD)method is used to study light-modulated characteristics of two-dimensional photonic crystals composed of circular air cylinders.Reflection spectrums of two-dimensional photonic crystals with different hole diameters and distances between holes were simulated with optical software.Two-dimensional photonic crystals with a hole diameter 800 nm,distance between holes 800 nm,depth of holes 400 nm had good angle-dependent structural color.In the experiment,a Cr-SiOx two-layer structure was prepared on Si substrates by magnetron sputtering.Photonic crystals were fabricated using a photolithography method.The experiment results matched the simulation results.