Prof. Gilad Haran (WIS)
Chemical and Biological Physics Department, Weizmann Institute of Science
Plasmonic structures concentrate electromagnetic fields to deep sub-diffraction volumes. Our lab has recently demonstrated that such nanofocusing can strongly couple plasmonic cavities and individual quantum emitters. In particular, we insert colloidal quantum dots into silver bowtie structures and study their spectroscopy. Indeed, light scattering spectra of individual devices clearly show a dip indicative of vacuum Rabi splitting, the hallmark of strong coupling. We find that fast electrons within the electron microscope can also probe this coupling through the phenomenon of electron energy-loss, but now with nanometric spatial resolution. Finally, photoluminescence of the coupled quantum dots shows that the interaction with the cavity can dramatically alter pathways of excited-state relaxation. Plasmonic strong coupling is thus established as a new testbed for quantum optics and chemical dynamics under ambient conditions.