Resonant Enhancement of Photoluminescence Intensity and Anisotropy of Quantum Dot Monolayers with Self-Assembled Gold Nanorods

Abstract

Quantum dot (QD) films are well known as promising materials for photo-detectors and photovoltaic and next generation display devices. In this study, we show, experimentally, how compact monolayer films of cadmium selenide (CdSe) QDs having compact assemblies of partially aligned metal nanorods placed in close proximity can be used to enhance the photoluminescence (PL) emission intensity by greater than ten times while the PL anisotropy can be increased to almost 0.9. Finite difference time domain (FDTD) simulations on smaller scale gold nanorod (GNR) arrays on CdSe QD layer not only explain this huge emission enhancement and anisotropy observed experimentally but also provide insight into the parameters which if further optimized can lead to even larger enhancement and emission anisotropy in similar hybrid systems. Our work paves the way for creation of large scale, simple and inexpensive, but highly efficient, metal nanorod-QD hybrid films which can find wide ranging potential applications in displays, detectors, and photovoltaics.