胶体光子晶体的平面介电常数缺陷

为引入特殊的光学性质,通常需要在三维光子晶体中人为可控地引入缺陷.通过改变局部结构单元的尺寸或介电常数,相应地引入给体或受体掺杂,带来不同的缺陷态.以前文献报道的向胶体光子晶体中引入缺陷,常会因为同时引入尺寸和介电常数掺杂,给掺杂性质的界定带来困难.本文中,我们结合对流自组装法和L-B膜法,在实心二氧化硅微球组成的三维光子晶体内引入尺寸相同的二氧化硅空心球(与实心球相比具有不同折光率)组成的单层平面缺陷,或者在空心球晶体内引入实心球缺陷层,构成实心-空心-实心或空心-实心-空心的三明治结构,在不破坏整体晶格的同时,在三维胶体光子晶体中引入单一的平面介电常数缺陷.

Colloidal Photonic Crystals with Planar Dielectric Defect

Artificially embedding defects into three-dimensional photonic crystals as designed, is a necessary way to introduce certain optical properties. Normally, donor defects or acceptor defects, with the difference size or dielectric constant with the surrounding units, result in corresponding defect modes in photonic band gap. In previous reports, size defect and dielectric defect are always introduced simultaneously, which makes it difficult to clarify the mode of defect. In this work, combining convective self-assembly and L-B film method, we embedded a monolayer of hollow silica microspheres as a planar defect layer in three dimensional photonic crystals of solid silica microspheres, or in the contrast, embedded monolayer of solid microspheres into colloidal crystals of hollow spheres. Since the sizes of solid and hollow silica microspheres are controlled as almost the same, in the fabricated colloidal photonic crystals with the embedded planar defect, namely sandwich structure, there is only dielectric defects existing, without size defects in periodic superlattices.