基于表面等离子体激元的微纳波导的光控研究

发布时间：2018-04-22 07:01

本文选题：表面等离子体 + 波导　；参考：《大连理工大学》2014年博士论文

【摘要】：为满足高速和高密度信息技术的需求,近年来,基于表面等离子体激元的纳米光子器件的研究呈现出迅猛发展的态势,利用其对光波在亚波长尺寸上进行操纵与控制已经成为国际上的研究热点问题之一。表面等离子体激元(Surface Plasmon Polaritons, SPPs),是在外加电磁场的诱导下,沿着介电常数符号相反的两种介质分界面传输的一种电磁表面波,其突出特点之一是能够打破传统光学器件波长衍射极限的限制,将电磁能量聚集在纳米尺度范围内,并且在金属内部具有极短的穿透深度(纳米级)。由于SPPs的亚波长局域、近场增强等特性,在纳米光子学中发挥着重要作用。目前世界上多个研究小组利用SPPs原理提出并在理论和实验上证明了金属-介质-金属(MIM)型波导结构具有超强的纳米光局域能力,并且在可见光区域内传输损耗低,制造容易,更适合高密度集成。本文主要利用离散偶极近似和时域有限差分这两种理论计算的方法研究微纳尺度的MIM功能型波导以及纳米天线,主要工作包括以下四个方面：一、提出了一种新型的腔体-通道波导结构,理论上证明了光路在微纳波导中的多次90。弯折。结构中,腔体内部引入的超薄金属膜作为光吸收装置,将更多的入射光能量耦合进入系统内部；通道部分作为导波系统把光传导出来。波导出口的位置及出口数量与光的传播或截止关系也作了详细地分析与阐述。该工作为微纳米尺度的光控提供了一种新的方法并且有望应用于光电器件的小型化。(第三章) 二、提出了一种光传播方向控制型波导--内嵌圆孔阵列的双层银膜波导结构。模拟结果显示：若圆孔阵列倾斜,在膜间距缩小到10nm时,该结构具有超高的方向选择性,且在结构共振时可有效地控制光传播方向；若圆孔阵列垂直双层膜,光波能够局域在截面积为10x20nm2的狭窄区域内有效地传播。此工作为亚波长尺寸的光传播方向控制与光压缩器件设计提供了新的方法。(第四章) 三、在近场纳米光刻掩模板的理论模型基础上,增加了凹槽结构,并对凹槽的参数及位置做了优化并深入讨论其物理机制,成功地将通道光刻的分辨率提高了3倍。加入凹槽改变了光刻通道出口处的表面等离子体激元波的相位分布,因此优化凹槽的参数可以达到有效地消除相邻通道之间干涉的目的,进而缩短通道之间的距离,提高掩模板的光刻分辨率。该改进后的结构可用于大面积高分辨率的光刻。(第五章) 四、对蝴蝶结纳米天线的光学特性进行了理论分析,将各个参数(张角、狭缝、顶端宽度、臂长和厚度)对电场增强因子以及共振波长的影响进行了详细地分析讨论,并对比偶极天线的情况,探究其中的物理机制。该计算结果及所得出的结论为今后进行表面增强拉曼散射研究等实验上设计合适的蝴蝶结天线具有指导意义。(第六章)
[Abstract]:In order to meet the needs of high speed and high density information technology, the research of nano-photonic devices based on surface plasmon has been developing rapidly in recent years. It has become one of the hot issues in the world to manipulate and control the subwavelength size of light waves. Surface Plasmon Polaritons, SPPsO, is an electromagnetic surface wave propagating along the interface of two dielectric media with opposite dielectric constant under the induction of an external electromagnetic field. One of its outstanding characteristics is that it can break through the limit of wavelength diffraction of traditional optical devices, gather electromagnetic energy in the nanoscale range, and have a very short penetration depth (nanoscale) in the metal. SPPs plays an important role in nanometer photonics due to its subwavelength localization and near field enhancement. At present, many research groups in the world have proposed and proved theoretically and experimentally that the metal-dielectric-metal Mimm waveguide structure has super local ability of nanometer light, and the transmission loss in visible region is low, so it is easy to manufacture. More suitable for high density integration. In this paper, MIM functional waveguides and nanoscale antennas are studied by using discrete dipole approximation and finite-difference time-domain (FDTD) methods. The main work includes the following four aspects: Firstly, a novel cave-channel waveguide structure is proposed. Bend. In the structure, the ultra-thin metal film introduced in the cavity is used as the optical absorption device, and more incident light energy is coupled into the system, while the channel part acts as the guided wave system to transmit the light out. The relationship between the position and the number of the waveguide outlet and the propagation or cut-off of light is also analyzed and explained in detail. This work provides a new method for micro-and nano-scale optical control and is expected to be applied to the miniaturization of optoelectronic devices. (chapter III) Secondly, a double-layer silver film waveguide structure with a circular hole array embedded in the waveguide is proposed. The simulation results show that if the circular aperture array tilts and the membrane spacing is reduced to 10nm, the structure has ultra-high directional selectivity and can effectively control the direction of light propagation when the structure resonates; if the circular aperture array is perpendicular to the bilayer film, Light waves can propagate locally in a narrow area with a cross-sectional area of 10x20nm2. This work provides a new method for the control of optical propagation direction and the design of optical compression devices with sub-wavelength size. (chapter IV) Thirdly, based on the theoretical model of near-field nanocrystalline lithography, the groove structure is added, and the parameters and position of the grooves are optimized and its physical mechanism is discussed. The resolution of channel lithography is improved by three times successfully. Adding grooves changes the phase distribution of surface plasmon waves at the exit of lithography channels, so optimizing the parameters of grooves can effectively eliminate the interference between adjacent channels and thus shorten the distance between channels. Improve lithography resolution of mask. The improved structure can be used for large area high resolution lithography. (chapter V) Fourthly, the optical characteristics of the bow nanowire antenna are theoretically analyzed, and the effects of various parameters (angle, slit, top width, arm length and thickness) on the electric field enhancement factor and resonance wavelength are analyzed and discussed in detail. The physical mechanism of the dipole antenna is discussed. The calculated results and the conclusions obtained are of guiding significance for the design of suitable bow-knot antennas in future experiments such as surface enhanced Raman scattering. (chapter VI)
【学位授予单位】：大连理工大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：TN814

【共引文献】