CAREER: Towards Novel Twist Polaritonics in 2D Crystals and Devices

该奖项全部或部分根据2021年美国救援计划法案（公法117-2）资助。非技术描述：表面极化激元是一种由光（光子）与界面电偶极子强耦合产生的混合量子粒子。这些高度受限的纳米光波具有单独存在于单独组件中不存在的涌现特性，使它们有可能实现用于传感，通信和信息处理的新型电路。在纳米尺度上捕获光以产生和操纵这些极化子波是必不可少的。研究人员将通过堆叠和扭曲特定的2D层，对一类具有独特原子排列的工程二维（2D）量子器件中空间受限的纳米光的流动进行成像。这项研究将揭示这些独特结构中发生的纳米光波传播的新特性。该团队希望利用极化子波来揭示2D材料和设备中迷人的新物理学，并为新型量子纳米光子技术铺平道路。PI计划将研究与各种教育和推广活动相结合，以指导K-12，本科和研究生水平的学生，特别是那些来自代表性不足的少数群体的学生。该团队还将参加由佛罗里达州立大学和国家高磁场实验室联合为公众提供的二维材料和纳米光学综合推广计划。该项目由材料研究部（DMR）的电子与光子材料（EPM）和凝聚态物理（CMP）项目联合资助。技术描述：该团队的目标是在前所未有的长度尺度上突破光物质相互作用的极限，并利用发射的极化子波来阐明和控制二维（2D）量子器件中出现的拓扑状态。主要重点是二维货车德瓦尔斯异质结构和双电子，一个高度可调的拓扑平台，拥有一整套不同的极化激元模式（等离子体，声子等）。其可以与远低于衍射极限的入射光子强烈耦合。国家的最先进的扫描近场光学显微镜技术将进行直接发射和可视化极化子波，因为他们沿着沿着二维扭曲层旅行到纳米长度尺度在所需的长波长光子激发。特别是，实空间极化激元纳米成像赠款访问高光子动量空间，这是远远超出了传统的远场光学所能达到的。利用这种独特的扫描近场技术，项目组计划1）寻找新型拓扑极化激元的特征，并研究其在二维量子器件中的内在特性; 2）通过调节相对扭转角和原位电位移场，探索通过莫尔超晶格势对拓扑极化激元的有效控制和操纵;以及3）通过跨多个维度的多信使纳米探针表征来理解红外/太赫兹低能尺度下的新物理和奇异量子现象。这项研究有望加深我们对拓扑极化激元如何产生和利用来探测量子固体的理解，并利用纳米光的长寿命无耗散流动用于未来的应用，包括量子传感和通信，拓扑激光器和量子电路在2D扭曲系统和超越。这个奖项反映了NSF的法定使命，并已被认为是值得支持，通过评估使用基金会的学术价值和更广泛的影响审查标准。

This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2). Nontechnical Description: Surface polaritons are a type of hybrid quantum particles resulting from light (photons) strongly coupled to interfacial electric dipoles. These highly confined nano-light waves have emergent properties that do not exist in the separate components alone, giving them the potential to realize novel circuitry for sensing, communications, and information processing. It is essential to trap light at the nanoscale to generate and manipulate these polaritonic waves. The investigators will image the flow of spatially confined nano-light in a class of engineered two-dimensional (2D) quantum devices with a unique atomic arrangement by stacking and twisting specific 2D layers. This research will uncover the novel characteristics of propagating nano-light waves that occur within these unique structures. The team expects to harness polaritonic waves to shed light on the fascinating new physics in 2D materials and devices and pave the way for new types of quantum nano-photonic technologies. The PI plans to integrate research with various education and outreach activities to mentor students at the K-12, undergraduate and graduate levels, especially those from underrepresented minority groups. The team will also participate in integrated outreach programs on 2D materials and nano-optics for the general public offered jointly by Florida State University and the National High Magnetic Field Laboratory. This project is jointly funded by the Electronic and Photonic Materials (EPM) and the Condensed Matter Physics (CMP) programs of the Division of Materials Research (DMR).Technical Description: The team aims to push the limits of light-matter interactions at unprecedented length scales and employ the emitted polaritonic waves to elucidate and control emergent topological states in two-dimensional (2D) quantum devices. The primary focus is on 2D van der Waals heterostructures and twistronics, a highly tunable topological platform that hosts a full suite of different polaritonic modes (plasmons, phonons, etc.) that can strongly couple with the incident photons far below the diffraction limit. State-of-the-art scanning near-field optical microscopy techniques will be carried out to directly launch and visualize polaritonic waves as they travel along 2D twisted layers down to the nanometer length scale at the desired long-wavelength photon excitations. In particular, real-space polaritonic nano-imaging grants access to the high photon momentum space that is far beyond what is attainable with conventional far-field optics. With this unique scanning near-field technique, the project team plans to 1) look for signatures of novel topological polaritonics and investigate their intrinsic characters in 2D quantum devices; 2) explore effective control and manipulation of topological polaritons through the moiré superlattice potential by tuning the relative twist angles and in situ electrical displacement fields; and 3) understand the new physics and exotic quantum phenomena at the infrared/terahertz low energy scales through multi-messenger nano-probe characterizations across multiple dimensions. The research is expected to deepen our understanding of how the topological polaritons can be generated and utilized to probe quantum solids, and harnessing long-lived dissipation-less flow of nano-light for future applications including quantum sensing and communication, topological lasers and quantum circuitry in 2D twisted systems and beyond.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.