ABSTRACT
Despite the significant progress in single-molecule fluorescence microscopy made, the efficient detection of a single molecule remains a major goal with applications in chemical, biochemical, and biophysical analysis. The phenomenon of light diffraction appears as a main physical limiting factor. In order to understand the phenomenon of enhanced fluorescence in the vicinity of a nanostructure, one has to go back to the representation of the quantum emitter as a two-energy-level system. To overcome the diffraction limit, nanoantenna designs take advantage of sharp curvature radii, nanoscale gaps and plasmonic resonances, using metal nanostructures. A large number of approaches have been investigated over the last decade in order to enhance the fluorescence emission of single molecules and quantum dots. Electron beam lithography focused ion beam milling or deep UV photolithography have a large flexibility in creating a variety of planar antenna designs at specific locations.
