Enhancing Plasmonic Spectral Tunability with Anomalous Material Dispersion

• DOI: 10.1021/acs.nanolett.0c03293
• Publication Date: 2020-12-21T18:51:38Z
• Authors: Mengjie Zheng; Yi Yang; Di Zhu; Yiqin Chen; Zhiwen Shu; Karl K. Berggren; Marin Soljačić; Huigao Duan
• Keywords: Gamut

The field confinement of plasmonic systems enables spectral tunability under structural variations or environmental perturbations, which is the principle for various applications including nanorulers, sensors, and color displays. Here, we propose demonstrate that materials with anomalous dispersion, such as Ge in visible, improve tunability. We introduce our proposal a semianalytical guided mode picture. Using Ge-based film (Ag/Au)-coupled gap plasmon resonators, implement two architectures improved single-particle dark-field scattering, ensemble reflection, generation. observe three-fold enhancement nanodisks compared Si, normal-dispersion material visible. generation large array systems, made inversely fabricated Ge–Ag exhibits wide gamut. Our results dispersion an extra degree freedom to engineer especially relevant actively tunable plasmonics metasurfaces.