Plasmonic Dimple Array from Self-Assembled Liquid Crystal Defect Structure

Abstract

Metal thin film with hole structures generally show the highly enhanced electromagnetic field from surface plasmon effect. Various lithography techniques have been adopted to fabricate well-defined and small feature sized metal-hole template for effective plasmonic substrates. In this study, uniform and well-ordered micro-dimple structure was fabricated by self-assembled liquid crystal (LC) defect structure, so called toric focal conic domain (TFCD). From the first and second replica molding by using NOA and PDMS, the dimple structure on the PDMS was formed. The thin gold layer was deposited on the PDMS dimple structure and it shows highly field enhancement phenomenon from the gold dimple structure. Enhanced fluorescence observation with quantum dot and FDTD simulation was performed to prove the effectiveness of plasmonic array.