Nichtlinieare plasmonische Nanoantennen aus Lithiumniobat

由铌酸锂制成的非线性等离子体纳米天线

• 批准号: 138526156
• 负责人: Professor Dr. Thomas Pertsch
• 金额: --
• 依托单位: Institut für Angewandte Physik
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2009
• 资助国家: 德国
• 起止时间: 2008-12-31 至 2016-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/138526156?language=en
• 关键词: Nichtlinieare; plasmonische; Nanoantennen; aus; Lithiumniobat

The successful exploration of nonlinear processes in nanostructured waveguides comprising lithium niobate in the first funding period led to a series of groundbreaking contributions. Examples are suggestions for novel phase matching schemes, clarifications on the ability to enhance the propagation length of surface plasmon polaritons guided in metallic waveguides by parametric amplification, but also adjacent topics were explored such as the first observation of an Airy-plasmon and the in-depth analysis of linear properties of optical nanoantennas. The challenging work that has been performed in a combined experimental and theoretical effort served the purpose to understand and to control the ultrafast nonlinear dynamics of light in optical nanostructures. In the second funding period, the methodology and the means previously developed will be used to study in a coherent continuation the ultrafast nonlinear dynamics of cavities made from finite metallic nanowaveguides embedded into a nonlinear surrounding made of nanostructured lithium niobate. The cavities essentially constitute optical nanoantennas where a guided mode bounces back and forth and eventually experiencing a resonant interaction where the plasmons suffering from multiple reflections constructively interfere. The raison d'être of these resonances are dictated by the phase accumulation of the plasmons propagating across the nanoantenna and a contribution from the phase of the complex reflection coefficient at the antenna termination. Both properties can be adjusted at will for the various frequencies involved in the nonlinear process by tailoring the geometrical cross section of the nanoantennas and the nanoantenna termination. This combination provides novel degrees of freedoms to achieve efficient nonlinear conversion inaccessible thus far. Moreover, the ability to tailor the radiation pattern of the optical nanoantennas will provide in perspective an integrated nonlinear light-source with directed emission and allows engineering parametric nonlinear processes well beyond the current state of the art by superimposing simultaneously various incidence fields. Based on the fundamental theoretical understanding and the developed experimental techniques we will target major challenges of the field, as e.g. Q-factor enhancement of plasmonic resonances by nonlinear parametric gain, generation of entangled photons in nanoantennas by spontaneous downconversion, or nanosized SHG light sources for high contrast sensor applications. The work we propose is an extension of our manifold activities in the previous funding period and fuses the leitmotifs and the main research direction of the priority program, i.e. nonlinearity, optical nanoantennas, propagation, and coherent control.

在第一个资助期，成功地探索了含有铌酸锂的纳米结构波导中的非线性过程，从而产生了一系列开创性的贡献。例如，建议新的相位匹配方案，阐明通过参数放大提高金属波导中表面等离子体激元传播长度的能力，但也探索了邻近的主题，如首次观测到艾里等离子体激元和深入分析光学纳米天线的线性特性。这项具有挑战性的工作是在实验和理论工作相结合的情况下进行的，目的是为了理解和控制光学纳米结构中的超快非线性光动力学。在第二个资助期，以前开发的方法和手段将被用来连贯地继续研究嵌入到由纳米结构的铌酸锂组成的非线性环境中的有限金属纳米波导腔的超快非线性动力学。这些空腔基本上构成了光学纳米天线，其中导模来回反弹，最终经历了共振相互作用，其中遭受多次反射的等离子体会建设性地干扰。这些共振存在的理由是由横跨纳米天线传播的等离子体的相位积累和天线端点处的复反射系数的相位贡献决定的。通过定制纳米天线和纳米天线终端的几何横截面，这两种特性都可以针对非线性过程中涉及的不同频率随意调整。这种组合提供了新的自由度，以实现到目前为止还无法实现的高效非线性转换。此外，定制光学纳米天线的辐射模式的能力将透视地提供具有定向发射的集成非线性光源，并通过同时叠加各种入射场来允许工程参数非线性过程远远超出当前技术状态。基于基本的理论理解和发展的实验技术，我们将针对该领域的主要挑战，例如通过非线性参数增益的Q因子增强等离子体共振，通过自发下转换在纳米天线中产生纠缠光子，或者用于高对比度传感器应用的纳米倍频光源。我们提出的工作是我们在前一个资助期的多种活动的延伸，融合了优先计划的主旨和主要研究方向，即非线性、光学纳米天线、传播和相干控制。