基于局域表面等离子体共振增强的硅纳米线光电流特性及其物理机制的研究

项目名称： 基于局域表面等离子体共振增强的硅纳米线光电流特性及其物理机制的研究

项目编号： No.51202300

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 无机非金属材料学科

项目作者： 陈焕君

作者单位： 中山大学

项目金额： 25万元

中文摘要： 贵金属纳米颗粒具有局域表面等离子体共振（LSPR）特性，处于共振激发时颗粒可以极大增强其周围的局域电场，同时将入射光强烈散射进入介质内部。这两个效应可以有效增强颗粒周围介质的光吸收。本申请项目将结合我们前期的研究基础，提出将金纳米棒与硅纳米线复合，利用金纳米棒的LSPR来提高硅纳米线自身的光吸收，从而实现其光电流的增强。将选择LSPR与硅纳米线泄漏光学模匹配的金纳米棒，采用化学组装的方法将其均匀组装到硅纳米线上，进而在单根复合结构上系统研究金纳米棒的体积、分布密度、金纳米棒与纳米线表面的间距、入射光的波长和偏振等对光电流的影响，获得LSPR对硅纳米线光电流增强的技术。基于实验结果，我们也将聚焦相关的物理问题，深入研究硅纳米线的泄漏光学模式与LSPR的电磁耦合效应，揭示光电流增强的物理机制。本研究将为解决硅纳米线光吸收弱这一制作硅基高灵敏度纳米光探测器的瓶颈问题提供理论依据和技术积累。

中文关键词： 局域表面等离子体共振；硅纳米线；金纳米棒；光电流；模式耦合

英文摘要： Noble metal nanoparticles exhibit extraordinary optical properties due to their localized surface plasmon resonances (LSPR), such as extremely large local electric field enhancement and strong light scattering. These properties can be efficiently utilized for enhancing the light absorption of the adjacent materials. In this proposal, we intend to improve the light absorption and thereafter the photocurrent of silicon nanowires through excitation of the localized surface plasmon resonances of gold nanorods that are homogeneously assembled onto the surface of the silicon nanowires. In our studies, the gold nanorods with plasmon wavelength in resonance with the leaky mode of silicon nanowire will first be homogeneously assembled onto an individual silicon nanowire using chemical method. The photocurrent of the hybrid nanostructure will then be measured to demonstrate the enhancement of the photocurrent by the plasmon resonances of the gold nanorods. The influence of various parameters, including the volume of the nanorods, the surface density of the nanorods on the silicon nanowire, the separation between the nanorods and the silicon surface, the wavelength and polarization of the incident light, will be systematically cultivated. Moreover, electrodynamic simulations will be employed to reveal the underlying mechan

英文关键词： Localized Surface Plasmon resonance；Silicon Nanowire；Gold Nanorod；Photocurrent；Mode Coupling