CAREER: Low-Loss and Tunable Optical Huygens Metasurfaces

非技术性描述：这个CAREER项目试图通过使用非常小的天线来控制光的行为，也被称为纳米结构超颖表面。该研究旨在最大限度地减少这些元表面的低效率，同时使用它们来控制按需照明的行为。首席研究员设想应用太阳能电池板可以收集更多的阳光，通信可以显著提高速度，智能手机相机镜头可以改进，窗户可以调整透明度以捕获或释放建筑物的热量，计算机显示器可以通过开关变成镜子。这项研究活动与培养下一代材料科学家和工程师的努力相结合，特别是通过推出新材料博士课程。此外，针对中学生的以指导为重点的暑期研究体验旨在扩大代表性不足的群体和大新奥尔良社区成员在科学研究和教育方面的参与。技术描述：需要基本的新材料见解来通过低损耗和易于调谐的光学超颖表面在纳米尺度上操纵光的相位和振幅。成功的平台可以作为一系列应用的关键构件，例如用于光通信的轨道角动量的高速编码。这个CAREER项目研究低损耗惠更斯超颖表面作为动态可调光学平台。超颖表面由光学纳米天线组成，它们与入射波的电场和磁场强烈相互作用。数值技术被用来设计由可调光学材料（如二氧化钒）组成的超颖表面。超表面是使用纳米纤维技术合成的。使用一套光学和材料分析工具来表征特性与调谐参数（例如电或热刺激），包括相移，光偏转和超快响应的测量。通过三个子任务研究这些材料的特性，分析单层超颖表面、多层超颖表面以及空间可寻址超颖表面的光学可调谐性。这些研究目标与教育工作相结合，强调指导和实践学习光子材料的学生在中学到研究生水平。活动包括开发新的课程内容，一个新的材料博士课程，高中生的材料夏令营，和中学生的研究经验。

Nontechnical description: This CAREER project seeks to control the behavior of light by using very small antennae, also known as nanostructured metasurfaces. The research seeks to minimize inefficiencies in these metasurfaces while using them to control the behavior of light on-demand. The principal investigator envisions applications where solar panels can harvest more sunlight, communications can function with significant enhancement in speed, smartphone camera lenses can be improved, windows can adjust their transparency to trap or release heat from buildings, and computer displays can become mirrors with the flick of a switch. This research activity is integrated with efforts to train the next generation of materials scientists and engineers, specifically through the launch of a new materials PhD program. In addition, a mentoring-focused summer research experience for middle school students aims to broaden the participation of underrepresented groups, and members of the greater New Orleans community in general, in science research and education.Technical description: Fundamental new materials insights are required to manipulate the phase and amplitude of light at the nanoscale through optical metasurfaces that are both low-loss and easily tunable. Successful platforms may serve as a key building block for a range of applications, such as high speed encoding of orbital angular momentum for optical communications. This CAREER project investigates low-loss Huygens metasurfaces as a platform for dynamically tunable optics. The metasurfaces are composed of optical nanoantennae that strongly interact with both the electric and magnetic fields of incident waves. Numerical techniques are used to design metasurfaces composed of tunable optical materials such as vanadium dioxide. Metasurfaces are synthesized using nanofabrication techniques. Properties are characterized vs. tuning parameter (e.g. electrical or thermal stimulus) using a suite of optical and materials analysis tools, including measurement of phase shift, light deflection, and ultrafast response. Properties of these materials are investigated through three subtasks, analyzing optical tunability in single-layer metasurfaces, multi-layer metasurfaces, as well as spatially addressable ones. These research objectives are integrated with educational efforts that emphasize mentoring and hands-on learning about photonic materials for students in middle school through the graduate level. Activities include developing new course content, a new materials PhD program, a materials summer camp for high school students, and research experiences for middle school students.