Materials World Network: Nonlinear Optical Metamaterials-Fabrication, Characterization, Theory

该项目对一种新型的人工非线性纳米光子材料进行研究，该材料利用研究人员的能力，将纳米加工与材料的本征性质结合起来，来定制这些超材料的光学响应。对超材料非线性光学性质的全面理解和实验实现的主要挑战是，超材料的表面和体非线性光学理论尚未发展，也缺乏制造和测试这种理论的实用手段。这种合作的主要理由是，它与伦敦大学学院的一个强大的英国团队和哥伦比亚大学的一个美国团队相匹配，前者在非线性光学和聚焦离子制造方面拥有强大的理论能力，后者在集成和等离子制造、光学测试和材料制备方面有着良好的记录。与布鲁克海文国家实验室(BNL)纳米中心的互动以及与伦敦纳米技术中心的互动对制造也很重要。感兴趣的材料包括铁电和等离子金属中的周期性纳米结构。研究了几种纳米结构，包括光子晶体、负折射率超材料，以及利用薄膜中的电光效应对这些材料进行调谐。我们还研究了一些新的理论方面，包括等离子体散射中的非线性效应和薄膜中光吸收的等离子体增强效应。首先，它促进了对人造非线性超材料的基础材料科学的跨学科审查，包括制造和生长、材料物理、光学物理和理论。其次，它使美国和英国的两个组织能够进行合作，这两个组织有着丰富的互动历史以及互补的专业知识和能力。这项工作为研究生和本科生提供了在国际环境中合作和旅行的机会。第三，该项目有具体的计划和程序，通过四次面向哥伦比亚大学本科生的外联讲座和一次在英国伦敦大学学院的外联讲座，寻求招募不同的学生合作者。它还使学生能够积极参与哥伦比亚大学的本科生研究机会计划(UROP)。第四，该项目使学生能够通过延长访问和缩短行程与新成立的纳米中心和伦敦纳米技术中心的主要美国国家实验室(即布鲁克海文)进行合作。

This project conducts research into a new class of artificial nonlinear nanophotonic materials, which makes use of the investigators ability to use nanofabrication in conjunction with intrinsic materials properties to tailor the optical response of those metamaterials. The main challenges towards a comprehensive understanding and experimental realization of nonlinear optical properties of metamaterials are that a theory of surface and bulk nonlinear optics of metamaterials is yet to be developed, and a practical means to fabricate and test such a theory is missing as well. The central rationale for this collaboration is that it matches a strong UK group at University College London with demonstrated theoretical capabilities in nonlinear optics and focused-ion-based fabrication capabilities, with a US group at Columbia University with a demonstrated record of integrated and plasmonic fabrication, optical testing, and materials preparation. Interactions with the Brookhaven National Laboratory (BNL) Nanocenter as well as that with the London Centre for Nanotechnology are also important for fabrication. The materials of interest include periodic nanostructures in ferroelectrics and in plasmonic metals. Several nanophotonic structures are examined, including photonic crystals, negative index metamaterials, and tuning of these materials using electrooptical effects in thin membranes. New theoretical aspects are also examined, including nonlinear effects in plasmonic scattering and plasmonic enhancement of optical absorption in thin films.The research undertaken here has several areas of broad impact. First, it fosters an interdisciplinary examination of the fundamental materials science of artificial nonlinear metamaterials, including fabrication and growth, materials physics, optical physics, and theory. Second, it enables two groups in the US and the UK, with a strong history of interactions and complementary expertise and capabilities, to collaborate. This work involves the opportunity for both graduate and undergraduate students to collaborate and travel in an international setting. Third, the project has concrete plans and procedures to seek out recruitment of diverse student collaborators via four outreach talks to undergraduates at Columbia University and one outreach talk at University College London, UK. It also enables active participation of students in the undergraduate research opportunities program (UROP) at Columbia. Fourth, the project enables students to collaborate via extended visits and shorter trips with a major US National Laboratory, i.e. Brookhaven, in their new Nanocenter, as well as the London Centre for Nanotechnology.