Recent results have shown unprecedented control over separation distances between two metallic elements hundreds of nanometers in size, underlying the effects of free-electron nonlocal response also at mid-infrared wavelengths. Most of metallic systems however, still suffer from some degree of inhomogeneity due to fabrication-induced surface roughness. Nanoscale roughness in such systems might hinder the understanding of the role of microscopic interactions. Here we investigate the effect of surface roughness in coaxial nanoapertures resonating at mid-infrared frequencies. We show that although random roughness shifts the resonances in an unpredictable way, the impact of nonlocal effects can still be clearly observed. Roughness-induced perturbation on the peak resonance of the system shows a strong correlation with the effective gap size of the individual samples. Fluctuations due to fabrication imperfections then can be suppressed by performing measurements on structure ensembles in which averaging over a large number of samples provides a precise measure of the ideal system's optical properties.
Seeing inside a Plasmonic Nanogap: Few-molecule Orientation and Preferential Adsorption
Ecole Polytechnique Fédérale de Lausanne (EPFL)（洛桑联邦理工学院）；Center for Quantum Science and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL)（洛桑联邦理工学院量子科学与工程中心）
Extreme mid-infrared field enhancement and anapoles in high-index plasmonic metamaterials
School of Physics and Astronomy, University of Birmingham（伯明翰大学物理与天文学学院）；NanoPhotonics Centre, Cavendish Laboratory, University of Cambridge（剑桥大学卡文迪许实验室纳米光子学中心）
Crystalline metal flakes: Platforms for advanced plasmonics and hybrid 2D material architectures
Swiss Federal Institute of Technology Lausanne (EPFL)（洛桑联邦理工学院）；Universität Würzburg（维尔茨堡大学）；Leibniz Institute of Photonic Technology（莱布尼茨光子技术研究所）；University of Southern Denmark（南丹麦大学）
Toroidal Plasmonic Nanodimers for Enhanced Near-Infrared Emission in Heterostructured InP Quantum Dots
Bilkent University（比尔肯特大学）；UNAM - National Nanotechnology Research Center and Institute of Materials Science and Nanotechnology, Bilkent University（比尔肯特大学纳米科学与技术国家研究中心与材料科学和纳米技术研究所）
Material-Specific Mapping of Plasmonic Modal Dispersion via Discrete Momentum-Space Probes
Moulay Ismail University（穆莱·伊斯梅尔大学）；Laboratory of Optics, Information Processing, Mechanics, Energetics and Electronics, Department of Physics, Moulay Ismail University（光学、信息处理、力学、能源与电子实验室，物理系，穆莱·伊斯梅尔大学）；Institut d’Electronique, de Microélectonique et de Nanotechnologie, UMR CNRS 8520, Département de Physique, Université de Lille（电子、微电子和纳米技术研究所，CNRS联合研究单位8520，物理系，里尔大学）
