title: Photoluminescence enhancement of quantum dots on Ag nanoneedles.
abstract: Noble metal nanostructure allows us to tune optical and electrical properties, which has high utility for real-world application. We studied surface plasmon-induced emission of semiconductor quantum dots (QDs) on engineered metallic nanostructures. Highly passive organic ZnS-capped CdSe QDs were spin-coated on poly-(methyl methacrylate)-covered Ag films, which brought QDs near the metallic surface. We obtained the enhanced electromagnetic field and reduced fluorescence lifetimes from CdSe/ZnS QDs due to the strong coupling of emitter wave function with the Ag plasmon resonance. Observed changes include a six-fold increase in the fluorescence intensity and striking reduction in fluorescence lifetimes of CdSe/ZnS QDs on rough Ag nanoneedle compared to the case of smooth surfaces. The advantages of using those nanocomposites are expected for high-efficiency light-emitting diodes, platform fabrication of biological and environmental monitoring, and high-contrast imaging.
authors.affiliation: Department of Nano Fusion Technology, College of Nanoscience and Nanotechnology, Pusan National University, Miryang, 627-706, Korea. jaebeom@pusan.ac.kr.
authors.forename: Syed Rahin
authors.initials: SR
authors.lastname: Ahmed
authors.forename: Hee Ryoung
authors.initials: HR
authors.lastname: Cha
authors.forename: Jung Youn
authors.initials: JY
authors.lastname: Park
authors.forename: Enoch Y
authors.initials: EY
authors.lastname: Park
authors.forename: Dongyun
authors.initials: D
authors.lastname: Lee
authors.forename: Jaebeom
authors.initials: J
authors.lastname: Lee