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.

在第一期资助期间，对铌酸锂纳米结构波导非线性过程的成功探索带来了一系列突破性的贡献。例如，对新颖的相位匹配方案的建议，对通过参量放大增强金属波导中引导的表面等离子体激元的传播长度的能力的澄清，而且还探讨了相邻主题，例如艾里等离子体激元的首次观察和光学纳米天线线性特性的深入分析。通过实验和理论相结合的方式进行的具有挑战性的工作旨在理解和控制光学纳米结构中光的超快非线性动力学。在第二个资助期间，先前开发的方法和手段将用于以相干延续的方式研究由嵌入纳米结构铌酸锂制成的非线性周围的有限金属纳米波导制成的空腔的超快非线性动力学。这些空腔本质上构成了光学纳米天线，其中导模来回反射，并最终经历共振相互作用，其中遭受多次反射的等离激元产生相长干涉。这些谐振存在的理由取决于纳米天线上传播的等离子体激元的相位累积以及天线终端处的复反射系数的相位的贡献。通过定制纳米天线和纳米天线终端的几何横截面，可以针对非线性过程中涉及的各种频率随意调整这两种属性。这种组合提供了新颖的自由度，以实现迄今为止无法实现的高效非线性转换。此外，定制光学纳米天线辐射图的能力将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，允许工程参数非线性过程远远超出当前技术水平。基于基本的理论理解和发达的实验技术，我们将针对该领域的主要挑战，例如通过非线性参数增益增强等离子体共振的 Q 因子，通过自发下转换在纳米天线中生成纠缠光子，或用于高对比度传感器应用的纳米级 SHG 光源。我们提出的工作是我们在上一个资助期间的多项活动的延伸，融合了优先计划的主题和主要研究方向，即非线性、光学纳米天线、传播和相干控制。