Applied Physics Seminar: Single-molecule microscopy and spectroscopy of plasmon-coupled fluorescence

Single-molecule microscopy and spectroscopy probe fluorescence emission in a direct, sensitive, and precise fashion. These measurements therefore enable us to observe and understand the strong light/matter interactions that occur when a dye molecule couples to the local surface plasmon resonance modes of a proximal metal nanoparticle. We have demonstrated improved brightness and photostability of dye molecules near gold nano-antennas, and we have extended this biocompatible fluorescence enhancement to fluorescent proteins in living cells. Furthermore, we have discovered that dye/nanoparticle coupling leads to a predictable mislocalization of the emission position and we are understanding the shifts in localization, polarization, and spectrum that arise in plasmon-coupled fluorescence. Overall, we are creating a flexible technology for super-resolution, real-time imaging.