Tuning and mapping hybrid polaritons at the nanoscale

在纳米尺度上调谐和映射混合极化子

• 批准号: 449639588
• 负责人: Dr. Katja Höflich
• 金额: --
• 依托单位: Ferdinand-Braun-Institut gGmbH, Leibniz-Institut für Höchstfrequenztechnik (FBH)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/449639588?language=en
• 关键词: Tuning; mapping; hybrid; polaritons; nanoscale

This project aims at the investigation of 'optical properties emergingfrom interlayer interactions in 2D vdW materials'. By combiningcutting-edge nanopatterning with nanoscale analysis we will ultimatelyrealize hybrid polaritonic modes with nanoscale confinement and lowlosses for possible applications in light-based future informationtechnology. In two-dimensional (2D) materials light-matter interaction canbe significantly enhanced by polaritons. A polariton is a quasiparticlethat results from coupling between an electro-magnetic wave, such aslight, and a dipole carrying excitation in matter. ‐ Typical matterexcitations are collective oscillations of free electrons (surfaceplasmon polaritons), lattice vibrations (phonon polaritons) or liftingelectrons from the valence to the conduction band (excitonpolaritons). Polaritons lead to changes in charge transport, chemicalreactivity and local potentials but may also provide for extreme lightlocalization and an enhanced density of electromagnetic states.Stacking of different 2D materials enables coupling of polaritons tohybrid modes with a large degree of tunability in the type of excitation,their coupling strength, and their localization and propagationbehaviour. Thereby, 2D heterostructures can serve for on-demanddesign of extraordinary physical properties. Here, we propose to tunehybrid modes of plasmons and phonons in 2D heterostructures fromsingle-crystalline silver or graphene with hexagonal boron nitride(hBN). He ion beam nanopatterning will allow to modify geometrieswith an accuracy <5 nm for the precise adjustment of both, theseparate excitations and the coupling strength between them. Usinglow-loss scanning transmission electron microscopy (STEM) electronenergy-loss spectroscopy (EELS), complete dispersion relations willbe obtained. Hybrid modes will be mapped with a simultaneousspatial resolution of <1 nm, energy resolution of <6 meV, andmomentum resolution of <0.2 nm-1. By using the electron beam as apulse and a probe simultaneously to excite and probe selectedmodes, unprecedented spatial and energy resolution will be combinedwith fs temporal resolution. Given the extremely high spatial resolutionof both, fabrication and analysis techniques, a large parameter spacefor investigation will be realized on a single sample.

该项目的目的是投资“从2D VDW材料中层间相互作用出现的光学性质”。通过将切口边缘纳米反映与纳米级分析相结合，我们将最终将混合极化模式与纳米级限制和低斜率相结合，以用于基于光的未来信息技术中的可能应用。在二维（2D）材料中，轻度 - 物质相互作用可以显着增强。极化子是由电磁波（例如光）和物质上携带令人兴奋的偶极子之间的偶联引起的quasiparticlethat。 - 典型的物质兴奋是自由电子（表面上极化子）的集体振荡，晶格振动（声子极化子）或从价到传导带（excitonpolaritons）的升力振动。极性子导致电荷运输，化学反应性和局部潜力的变化，但也可能提供极端的灯光定位和增强的电磁状态密度。堆叠不同的2D材料可以使极性构成与杂化模式的耦合，并在兴奋类型中与其耦合的强度和bepagiation和传播相结合。因此，2D异质结构可以用于非凡的物理特性的按住界面。在这里，我们建议使用硝化氢硼（HBN）中的2D异质结构中的血浆和声子模式。离子束纳米图案将允许以<5 nm的精度修改几何形状，以精确调整它们之间的兴奋和它们之间的耦合强度。使用LOSS-LOSS扫描透射电子显微镜（STEM）电子损失光谱（EELS），将获得完整的分散关系。杂种模式将以<1 nm的简单空间分辨率，<6 meV的能量分辨率，<0.2 nm-1的分辨率进行映射。通过将电子束用作APULSE，并且仅将探针刺激和探测选定的模式，前所未有的空间和能量分辨率将与FS临时分辨率结合使用。鉴于制造和分析技术的空间分辨率极高，将在单个样本上实现大量参数空间。