RUI: Unraveling Novel Nanophotonic Effects in Mid-Index Micro-Sized Dielectric Materials

RUI：揭示中折射率微米介电材料中的新型纳米光子效应

• 批准号: 2208240
• 负责人: Uttam Manna
• 金额: $ 28.82万
• 依托单位: Board of Trustees of Illinois State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-01 至 2025-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2208240&HistoricalAwards=false
• 关键词: RUI; Unraveling; Novel; Nanophotonic; Effects

NON-TECHNICAL SUMMARY:When light interacts with matter, a number of things can happen – it can be absorbed, reflected, scattered, or transmitted. If matter has nanoscale features, light-matter interactions can lead to interesting phenomena. For example, optical anapoles can confine light energy within the volume of nanostructures. In the case of zero back scattering (ZBS), light is preferentially scattered in the forward direction. The emerging field of nanophotonics puts such phenomena to use in applications such as solar energy, imaging, medicine, optical communications, and data storage. However, observation of these novel nanophotonic effects is currently restricted to materials with a high refractive index, such as silicon and germanium, and requires features sizes on the nanometer scale. The research team at Illinois State University (ISU) plans to demonstrate these effects in mid-index materials, such as titanium dioxide and diamond, with micrometer scale features. This research will push the boundary in terms of availability of materials and their size well beyond the current limit for observation of these novel nanophotonic effects. In the long run, the knowledge gained from the team’s research could be used to develop more efficient optical and photonic devices, such as photodetectors and nanolasers. The PI will work to broaden the workforce in optics and photonics by training undergraduate students in research and integrating the results of this research project into the physics curriculum. Participation of underrepresented minorities in STEM will be encouraged by using existing ISU infrastructure to recruit and train underrepresented students, including outreach to local high school students.TECHNICAL SUMMARY:Resonant optical excitation of high refractive-index dielectric particles offers unique opportunities to demonstrate novel nanophotonic effects such as nonradiating anapole states, optimum forward scattering, and magnetic hotspot enhanced Purcell effects. These novel nanophotonic effects observed are related to the excitation of single dipolar modes in high-index lossless dielectric materials. These effects are inaccessible for microscale objects due to the contributions from higher order multipolar modes under plane wave illumination. Hence, observation of nanophotonic effects is currently restricted to a few relatively high-index materials in the limit of nanometer size – typically within silicon and germanium. It was recently theoretically predicted that one can unravel dipolar regimes in homogenous high-index spheres with a wide range of size parameter and refractive indices under illumination. The research team at Illinois State University (ISU) plans to experimentally unravel the dipolar regime, excite non-radiating anapole states, and demonstrate zero backscattering in mid-index (1.5 n 3.0) dielectric spheres in the micrometer range under illumination with tightly focused Gaussian beams (TFGBs). TFGBs selectively excite a few relevant Mie coefficients and control the relative weight of the different multipolar modes of the incident field. This approach will enable the investigators to unravel the dipolar regime and associated novel nanophotonic effects in microscale homogenous spheres in the mid-index regime. Understanding these phenomena opens up enormous possibilities in terms of availability of materials and objects with size parameters well beyond the current physical picture for related nanophotonic applications.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

非技术摘要：当光与物质相互作用时，可能会发生许多事情 - 它可以被吸收，反射，分散或传播。如果物质具有纳米级特征，则光 - 摩擦相互作用会导致有趣的现象。例如，光学上可以将光能限制在纳米结构的体积中。在零后散射（ZB）的情况下，光线优选沿向前方向散射。纳米光子学的新兴领域将这种现象用于在太阳能，成像，医学，光学通信和数据存储等应用中使用。然而，目前对这些新型纳米光效应的观察仅限于具有高折射率的材料，例如硅和锗，并且需要在纳米表尺度上的特征大小。伊利诺伊州立大学（ISU）的研究团队计划在具有千分尺特征的中间指数材料（例如二氧化钛和钻石）中证明这些影响。这项研究将以材料的可用性及其大小为止，远远超出了目前观察这些新型纳米光子作用的限制。从长远来看，从团队的研究中获得的知识可用于开发更有效的光学和光子设备，例如光电探测器和纳米镜。 PI将通过培训本科生研究并将该研究项目的结果纳入物理学的研究结果来扩大光学和光子学的劳动力。 Participation of underrepresented minorities in STEM will be encouraged by using existing ISU infrastructure to recruit and train underrepresented students, including outreach to local high school students.TECHNICAL SUMMARY:Resonant optical excitement of high refractive-index dietary particles offers unique opportunities to demonstrate novel nanophotonic effects such as nonradiating anapole states, optimum forward scattering, and magnetic hotspot enhanced Purcell效果。观察到的这些新型的纳米光效应与无损失的顽固材料中单偶性模式的兴奋有关。由于平面波照明下高阶多极模式的贡献，这些效应对于微观对象而言无法访问。因此，目前对纳米光效应的观察仅限于纳米尺寸极限的一些相对高指数材料 - 通常在硅和锗内。最近的理论预测，可以在照明下具有广泛尺寸的参数和折射率范围的同质高指数领域中的偶极状态。伊利诺伊州立大学（ISU）的研究团队计划在实验中揭示偶极状态，激发非辐射的Anapole状态，并在微米范围内以紧密聚焦的高斯束（TFGB）（TFGBS）在微米范围内的中间折射率（1.5 N 3.0）中的反向散射（1.5 N 3.0）。 TFGB选择性地激发了一些相关的MIE系数，并控制入射场不同多极模式的相对重量。这种方法将使研究人员能够在Midscale同质球中揭示偶极状态和相关的新型纳米光效应。了解这些现象在材料和物体的可用性方面开辟了巨大的可能性，尺寸参数远远超出了当前的相关纳米光子应用的物理图片。该奖项反映了NSF的法定任务，并被认为是通过基金会的知识分子优点和更广泛的审查标准来通过评估来通过评估来支持的。