基于纳米结构Fano共振的可调谐多波长滤波技术研究

项目名称： 基于纳米结构Fano共振的可调谐多波长滤波技术研究

项目编号： No.61505144

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 无线电电子学、电信技术

项目作者： 刘菲

作者单位： 天津理工大学

项目金额： 20万元

中文摘要： 金属纳米结构的局部表面等离激元共振（LSPR）效应在光器件的设计制备方面已表现出优势。其中基于金属纳米结构LSPR效应的Fano共振，尤其是多重Fano共振谱的实现，已成为近几年该领域的一个研究热点。本申请旨在将多重Fano共振与双折射液晶分子相结合，利用液晶的电光效应，调控金属纳米棒聚合体的Fano共振，从而实现可调谐多波长滤波。研究包括基于金属纳米棒聚合体LSPR效应的多重Fano共振理论基础与光学特性研究；外加电压导致液晶介观相及折射率变化规律的研究；液晶相变对纳米棒聚合体Fano共振谱的调谐机理与性能研究。充分利用Fano共振损耗小的优势，减小滤波器的通带滚降，提高频谱效率。首先通过合理分析设计金属纳米棒聚合体的结构，得到偏振相关的多重Fano共振，实现多波长滤波；其次，通过合理设计电极排布，计算电压取值，利用电场调控液晶相变，实现滤波波长位置及个数的可调谐，从而提高滤波的灵活性。

中文关键词： 表面等离激元；Fano共振；多波长；电光效应；滤波

英文摘要： Localized surface plasmon resonance (LSPR) of metallic nanostructures has been demonstrated its potential in the design and fabrication of the optical devices. Fano resonance based on LSPR of nanostructures, especially multiple Fano resonances, has become a research hotspot in this field. The application combines the Fano resonances with the birefringent liquid crystal molecules. The electro-optic effect of liquid crystal is adopted to control the Fano resonances of metallic nanorod clusters, which can realize tunable multi-wavelength filtering. The research includes three parts: basic theory and optical characteristics of multiple Fano resonances of nanorod clusters based on LSPR, phase and refractive index changes of liquid crystal induced by driven electric field, and the tuning mechanism and filtering performance of the Fano resonances of nanorod clusters influenced by the liquid crystal. Based on the nonradiative characteristic of the Fano resonance, sharper rolloff in the passbands with larger spectrum efficiency can be obtained. The project combines the theory analysis with experiment verification. Firstly, multi-wavelength filtering is realized by designing the structure of nanorod clusters properly for the attainment of polarization-dependent multiple Fano resonances. Secondly, wavelength position and number can be tuned by the electric field controlled liquid crystal, with the well designed electrodes and calculated driven voltages. Therefore, the designed filtering could be more flexible.

英文关键词： Surface plasmon;Fano resonance;Multi-wavelength;Electro-optic effect;Filtering