胶体光子晶体带隙研究

Study of Photonic Band-Gap of Colloidal Photonic Crystals

以220 nm单分散聚苯乙烯微球悬浮液为原料,通过透析自组装、自然干燥制备胶体光子晶体。分别利用扫描电子显微镜和光纤光谱仪表征该晶体薄膜的微结构和光学特性。考察了光纤探头检测角度及溶剂渗透对样品衍射峰的影响。结果表明:所制备的胶体光子晶体具有良好的长程有序性,其衍射峰位置与光纤探头检测角度有关。研究还发现,通过有机溶剂二甲基硅油渗透晶体空隙可以改变光子晶体带隙位置和衍射强度,并通过有效填充率计算修正,验证了光子晶体带隙改变服从布拉格定律。

A colloidal photonic crystal was prepared by self-assembly and evaporation of 220 nm monodisperse PS latex. The microstructures and optical properties of colloidal photonic crystal were characterized by scanning electron microscope and fiber optic spectrometer, respectively. The influence of the Angle of the fiber probe and solvent penetration on the diffraction peak of the sample was investigated. The results showed that the colloidal photonic crystal has long-term ordered structure and whose diffraction peak has angle-dependent properties. The photonic band-gap of the colloidal photonic crystal could be shifted by infiltrate organic solvent, i.e.dimethyl silicone oil, into the vacancy of the crystal, which obeys the Bragg＇s law by calculating the packing rate of the PS colloids.