Plasmonic Nanowire-Enhanced Upconversion Luminescence for Anticounterfeit Devices

Abstract

A novel, efficient, cost-effective, and high-level security performance anticounterfeit device achieved by plasmonic-enhanced upconversion luminescence (UCL) is demonstrated. The plasmonic architecture consists of the randomly dispersed Ag nanowires (AgNWs) network, upconversion nanoparticles (UCNPs) monolayer, and metal film, in which the UCL is enhanced by a few tens, compared to reference sample, becuase the plasmonic modes lead to the concentration of the incident near infrared (NIR) light in the UCNPs monolayer. In the configuration, both the localized surface plasmons (LSPs) around the metallic nanostructures and gap plasmon polaritons (GPPs) confined in the UCNPs monolayer, significantly contribute to the UCL enhancement. The UCL enhancement mechanism resulting from enhanced NIR absorption, boosted internal quantum process, and formation of strong plasmonic hot spots in the plasmonic architecture is analyzed theoretically and numerically. More interestingly, a proof-of-concept anticounterfeit device using the plasmonic-enhanced UCL is proposed, through which a nonreusable and high-level cost-effective security device protecting the genuine products is realized.