Tunable Si-compatible Nonlinear Materials for Active Metaphotonics

非技术性描述：该项目推进了对具有可调光学特性和有效非线性行为的材料的理解，可能导致具有独特纳米级功能的光子器件。该研究小组利用实验和计算方法来帮助开发新型非线性光学材料和结构，使金属行为可控，用于下一代节能纳米光子器件，以及先进的光通信和硅芯片传感技术。该项目支持一名研究生，并鼓励本科生通过旨在将材料科学和光学工程的基本概念引入学术课程的推广工作参与研究，同时通过波士顿大学的暑期课程进行实际实验室演示和研究活动。外联计划的一个重要组成部分是通过参与该项目吸引代表性不足的少数群体从事材料科学和光学工程职业。最后，外展涉及一个重点教学模块的开发，解决光子材料的结构和光学特性。该模块每年与波士顿大学纳米技术创新中心合作，向波士顿大学光电中心的大学生以及工业界和学术界的从业者提供。技术说明：该项目的主要目标是开发可广泛调谐，低损耗和硅兼容的非线性等离子体材料，可用作集成在Si芯片上的下一代超材料器件的工程构建模块。这是通过控制掺杂，成分和微结构特性的过渡氧化物和氮氧化物陶瓷沉积的射频磁控溅射，然后热退火。这个为期三年的实验项目解决了关键的结构-性质关系，使等离子体近场的共振控制成为未来Si兼容可调谐元光子学的发展。特别是，该研究利用高分辨率能量过滤透射电子显微镜，基于实验室的X射线衍射，X射线吸收光谱，光谱学和电学特性，以阐明尚未未知的材料参数，这些参数导致光学损耗降低，光学非线性增强和可调金属色散跨越可见光到中红外的宽光谱范围。通过这样做，这项研究填补了基础材料理解的空白，允许创建具有独特特性和功能的新纳米结构。所提出的研究的智力价值依赖于非线性光学超材料的新型平台的开发，该平台可以解决限制金属基非线性超材料器件的低效非线性信号生成、缺乏可调谐性、热不稳定性和光学损耗等长期存在的问题。该项目能够产生更广泛的影响，因为它为下一代高度集成，具有成本效益的有源纳米等离子体芯片器件提供了基础，这些器件是信息处理，高度集成的非线性纳米光子学，光学传感和光谱学的关键组件。

Nontechnical description: This project advances the understanding of materials with largely tunable optical properties and efficient nonlinear behavior, potentially leading to photonic devices with unique nanoscale functionalities. The research team utilizes experimental and computational approaches to help develop novel nonlinear optical materials and structures that enable controllable metallic behavior, for use in next generation power-efficient nanophotonics devices, as well as in advanced optical communications and sensing technologies on silicon chips. The project supports one graduate student and encourages the involvement of undergraduate students in the research through an outreach effort aimed at introducing fundamental concepts of materials science and optical engineering into academic curricula, alongside practical laboratory demonstrations and research activities through summer programs at Boston University. An important component of the outreach plan is to attract underrepresented minorities to a career in materials science and optical engineering through participation in the project. Finally, the outreach involves the development of a focused teaching module, addressing the structural and optical properties of photonic materials. The module is offered yearly to college students as well as practitioners both in industry and academia at the Boston University Photonics Center, and in partnership with the Nanotechnology Innovation Center at Boston University. Technical description: The primary goal of this project is to develop widely tunable, low-loss and silicon-compatible nonlinear plasmonic materials that can be utilized as engineering building blocks for the next generation of metamaterial devices integrated atop Si chips. This is achieved by controlling doping, composition and microstructural properties of transition oxides and oxynitride ceramics deposited by radio frequency magnetron sputtering followed by thermal annealing. The experimental three-year project addresses critical structure-property relationships that enable resonant control of plasmonic near-fields for the future development of Si-compatible tunable metaphotonics. In particular, the research utilizes high-resolution energy filtered Transmission Electron Microscopy, laboratory-based X-ray diffraction, X-ray absorption spectroscopy, optical spectroscopy and electrical characterization in order to elucidate the yet-unknown materials parameters that lead to reduced optical losses, enhanced optical nonlinearity and tunable metallic dispersion across a wide spectral range spanning the visible to the mid-infrared. In so doing, this study fills gaps in foundational materials understanding, allowing the creation of new nanostructures with unique properties and functionalities. The intellectual merit of the proposed research relies on the development of a novel platform for nonlinear optical metamaterials that can solve the long lasting problems of inefficient nonlinear signal generation, lack of tunability, thermal instability and optical losses that limit metal-based nonlinear metamaterial devices. This project enables a substantial broader impact as it provides a foundation for the next generation of highly-integrated, cost-effective active nanoplasmonic on-chip devices that are crucial components in information processing, highly-integrated nonlinear nanophotonics, optical sensing and spectroscopy.