Enhanced fluorescence from metal nanoapertures: physical characterizations and biophotonic applications
Résumé
Nanoapertures milled in opaque metallic films offer a simple and robust photonic tool to significantly enhance the fluorescence of single molecules. We provide a detailed physical characterization of this phenomenon for apertures milled in gold and aluminum, and discuss its application to biophotonics. For the first time, the most general figures are provided to predict the awaited enhancement factors for almost every kind of fluorescent molecule. This knowledge is essential to discuss the ability to detect low-quantum yield species. We also report the first demonstration of single metal nanoapertures to perform DNA hybridization sensing, and measure similar enhancement factors as for experiments on diffusing molecules.