title: Resolution and enhancement in nanoantenna-based fluorescence microscopy.
abstract: Single gold nanoparticles can act as nanoantennas for enhancing the fluorescence of emitters in their near fields. Here we present experimental and theoretical studies of scanning antenna-based fluorescence microscopy as a function of the diameter of the gold nanoparticle. We examine the interplay between fluorescence enhancement and spatial resolution and discuss the requirements for deciphering single molecules in a dense sample. Resolutions better than 20 nm and fluorescence enhancement up to 30 times are demonstrated experimentally. By accounting for the tip shaft and the sample interface in finite-difference time-domain calculations, we explain why the measured fluorescence enhancements are higher in the presence of an interface than the values predicted for a homogeneous environment.
authors.affiliation: Laboratory of Physical Chemistry and optETH, ETH Zurich, CH-8093 Zurich, Switzerland.
authors.forename: Hadi
authors.initials: H
authors.lastname: Eghlidi
authors.forename: Kwang Geol
authors.initials: KG
authors.lastname: Lee
authors.forename: Xue-Wen
authors.initials: XW
authors.lastname: Chen
authors.forename: Stephan
authors.initials: S
authors.lastname: Götzinger
authors.forename: Vahid
authors.initials: V
authors.lastname: Sandoghdar
mesh_terms: D003198:Computer Simulation; D003287:Contrast Media / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008856:Microscopy, Fluorescence / Q000379:methods*; D008956:Models, Chemical; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media; D006046:Gold