EFRI NewLAW: Mid-infrared topological plasmon-polaritons with 2D materials

中红外光谱是一种技术上重要的光谱范围，用于识别生物和化学中的分子指纹、自由空间通信的大气透明窗口和与热有关的事件。拟议的研究包括在集体等离子体激元-极化激子激发中建立非平凡的拓扑(或表面相关)现象。这将为新型纳米光子组件(波导、分束器和其他)创造一个平台，这些组件可以支持中红外频率的非互易和理想的单向波传播。到目前为止，所有设计的光子拓扑绝缘体都涉及到块状铁磁材料、金属和电介质。这些超材料的特性是由设计预先定义的，是不可调谐的。我们的方法是利用电可调谐的量子材料及其等离子体激元-极化模式。例如，非互易等离子体激元-极化子模式的方向性可以在运行时进行电子控制。如果成功，这项研究将提供集成的中红外纳米光子学解决方案，如光学调制器、隔离器和路由器、片上中红外激光器以及手性生物分子的片上传感。在加强教育和外展方面，这项计划将实施三管齐下的扩大参与计划。首先，它将为参与的私人投资机构制定统一的行动计划，将量子材料纳米光子学纳入当前的本科课程，包括量子材料、光子学、光谱学和加工课程。其次，研究团队将为当地社区的K-12学生组织和建立暑期体验工作坊。第三，该团队将组织暑期班和额外的量子材料纳米光子学科学研讨会。这些活动将与该机构密切协调，并每年向NSF报告。其基态电子波函数中的非平凡Berry相最近启发了它在2D材料中的实验观测，例如山谷霍尔输运和带隙Dirac材料中的圆二向色性。然而，有人预测，电子基态的基本Berry相也应该给集体电子激发注入一种全新的非互易特征，即Berry等离子体。这个项目将研究两个基本问题：1)包括拓扑材料的等离子体-极化子在内的集体模是如何受到其单粒子电子态的非平凡拓扑的影响的？2)我们如何利用拓扑等离子体来创造新的光电子器件？为了回答这些问题，我们提出了一个理论和实验相结合的方案，目标如下：进行原理验证实验，验证预测的集体激发，Berry等离子体，并展示一套中红外纳米光子学组件，如能效的非互易光调制器和路由器，芯片上的中红外泵浦和探测激光器，以及用于手性生物分子传感的集成平台。该计划集成了凝聚态物理、材料和电磁建模、先进的逆光子系统设计、最先进的2D材料器件制造、先进的近场红外高光谱成像技术以及中红外集成光子学组件。这个为期4年的项目涉及明尼苏达大学、哥伦比亚大学、斯坦福大学和宾夕法尼亚大学。

The mid-infrared spectrum is a technologically important spectral range used for identifying molecular fingerprints in biology and chemistry, atmospheric transparent windows for free-space communications, and thermal-related events. The proposed research consists of establishing non-trivial topological (or surface-related) phenomena in collective plasmon-polaritonic excitations. This will then create a platform for novel nanophotonic components (waveguides, splitters, and others) which can support non-reciprocal and ideally unidirectional wave-propagation in the mid-infrared frequency. So far, all designs of photonic topological insulators involve bulk ferromagnetic materials, metals and dielectrics. The characteristics of these metamaterials are predefined by design and non-tunable. Our approach is to utilize electrically tunable quantum materials and their plasmon-polaritonic modes. For example, the directionality of the non-reciprocal plasmon-polaritons mode can be electrically controlled on-the-fly. If successful, this research would deliver integrated mid-infrared nanophotonics solutions, such as optical modulators, isolators and routers, on-chip mid-infrared lasers, and on-chip sensing of chiral biomolecules. On enhancing both education and outreach, this project will implement a three-pronged broadening participation program. First, it will employ a unified plan of action for the participating PIs to incorporate quantum materials nanophotonics into current undergraduate curricula, including classes in quantum materials, photonics, spectroscopy and processing. Secondly, the research team will organize and establish a summer experience workshop for K-12 students in the local communities. Third, the team will organize summer school and additional scientific workshops on quantum materials nanophotonics. These activities will be closely coordinated with the institution and reported to NSF annually.Non-trivial Berry phase in its ground state electronic wavefunction has recently inspired its experimental observation in 2D materials, such as valley Hall transport and circular dichroism in gapped Dirac materials. However, it was predicted that the underlying Berry phase of the electronic ground state should also imbue the collective electronic excitations with a completely new non-reciprocal character known as Berry plasmons. This project will investigate two fundamental questions: 1) How are the collective modes, including plasmons-polaritons of topological materials, impacted by the non-trivial topology of their single-particle electronic states? 2) How can we harness topological plasmons for creating new optoelectronic devices? To answer these questions, we propose a joint theoretical and experimental program, with the following goals; perform proof-of-principle experiments to verify the predicted collective excitation, Berry plasmons, and demonstrate a suite of mid-infrared nanophotonics components such as energy efficient non-reciprocal optical modulators and routers, on-chip mid-infrared pump and probe lasers, and integrated platform for sensing of chiral biomolecules. The program integrates condensed matter physics, materials and electromagnetics modeling, advanced inverse photonic system design, state-of-the-art 2D materials device fabrication, advanced hyperspectral imaging with near field infrared techniques, and mid-infrared integrated photonics components. This 4 years program involves University of Minnesota, Columbia University, Stanford University and University of Pennsylvania.