Scalable and controlled self-assembly of aluminum-based random plasmonic metasurfaces

• 来源期刊: 光：科学与应用（英文版）
• 关键词: aluminum plasmonics plasmonic metasurfaces polymer blends self-assembly SERS structural color
• 年，卷（期）: 2017,（3）
• 页码范围: 70-78
• 页数: 9页
• 语种: 英文
• DOI: 10.1038/Isa.2017.15

摘要

Subwavelength metal-dielectric plasmonic metasurfaces enable light management beyond the diffraction limit.However,a costeffective and reliable fabrication method for such structures remains a major challenge hindering their full exploitation.Here,we propose a simple yet powerful manufacturing route for plasmonic metasurfaces based on a bottom-up approach.The fabricated metasurfaces consist of a dense distribution of randomly oriented nanoscale scatterers composed of aluminum (Al) nanohole-disk pairs,which exhibit angle-independent scattering that is tunable across the entire visible spectrum.The macroscopic response of the metasurfaces is controlled via the properties of an isolated Al nanohole-disk pair at the nanoscale.In addition,the optical field confinement at the scatterers and their random distribution of sizes result in a strongly enhanced Raman signal that enables broadly tunable excitation using a single substrate.This unique combination of a reliable and lithography-free methodology with the use of aluminum permits the exploitation of the full potential of random plasmonic metasurfaces for diagnostics and coloration.