基于多层雕塑薄膜的亚波长高折射率差光栅高反射器件研究

Research of broadband, wide angular spectrum and polarization insensitivity reflectors used in visible and near-infrared spectral regions is one of the hot spots in the current field of photonic integrated circuits and optoelectronic devices. Based on the refractive index adjustment and birefringence of sculptured thin films, a new combined structure with sculptured thin films and sub-wavelength high-contrast grating is put forward in the project. The new reflector has excellent features of broadband, wide angular spectrum and polarization insensitivity. The main research aspects will include: research on the transmission mechanism of light in the structure and the combination mechanism of the sculptured thin films and the sub-wavelength high-contrast grating; research on the quantitative relations between the combined structure and its optical properties, and the optimal design of the broadband, wide angular spectrum, polarization insensitivity reflector; research on the preparation processes and the post-treatment of the reflector based on sculptured thin films. The innovative design for preparing the sub-wavelength high-contrast grating by using sculptured thin films improves phase-modulated performance to achieve broadband, wide angular spectrum and polarization insensitivity reflector. With the advantage of simple structure, easy to fabricate, the new sub-wavelength high-contrast grating reflector based on sculptured thin films is expected to promote the applications of new broadband grating reflectors in the optoelectronic system. And the new reflector has an extensive value of scientific research for the new sculptured thin film photoelectron devices.

寻求具有宽带、宽角谱、偏振无关特性的可见与近红外波段高反射器件是当前集成光路和光电子元件领域研究热点之一。本项目基于多层雕塑薄膜的折射率可调与双折射特性，提出雕塑薄膜与亚波长高折射率差光栅的混合结构，形成的新式高反射器件具备优良宽带、宽角谱和偏振无关高反射特性。主要研究内容包括：研究光在多层雕塑薄膜与亚波长高折射率差光栅混合结构的传播机制以及相互作用的机理；研究混合结构与光学特性的定量关系，优化获得宽带、宽角谱、偏振无关高反射器件设计；研究基于雕塑薄膜的光栅器件的制备工艺和后处理工艺。本项目创新地采用具有纳米结构的双折射率雕塑薄膜来制备亚波长光栅，使其具有更强相位调制能力，从而实现了宽带、宽角谱、偏振无关的高反射特性。这种新型的高反射器结构简单、易于生产，有助于推动新型宽带光栅器件在光电子集成系统的应用，为新式雕塑薄膜集成光电子器件的研究提供参考。

具有宽带特性的可见与近红外波段高反射器件是当前集成光路和光电子领域重要器件之一。围绕“宽带多层雕塑薄膜高折射率差亚波长光栅”这个核心任务，主要完成了以下工作:（1）首先，采用等效折射率方法，结合严格耦合波理论，分析了光栅的反射效率以及近电场分布；(2)采用多参数多目标优化方法优化了多层雕塑薄膜高折射率差亚波长光栅的结构参数，光栅的反射效率超过90%的带宽超过100nm，并考察了其工艺容差；（3）设计了多层雕塑金属膜偏振选择光栅，TE偏振光在0级全反射，TM偏振光在-1和0级按照1:1反射；（4）探索了制备雕塑薄膜光栅的工艺，并初步实现宽带光栅制备。此外，项目探索了基于光栅结构、二维材料薄膜和光纤的新型光电子器件。项目为新式雕塑薄膜集成光电子器件的研究提供了参考。