Photonic-Plasmonic Hybridization and Single-Particle Microresonator Spectroscopy | Randall Goldsmith

Photonic-Plasmonic Hybridization Explored via Single-Particle Microresonator Spectroscopy


Hybrid photonic-plasmonic systems have tremendous potential as versatile platforms for the study and control of nanoscale light-matter interactions since their respective components have either high quality factors or low mode volumes. Individual metallic nanoparticles deposited on dielectric optical microresonators provide an excellent example where ultrahigh-quality optical whispering-gallery modes can be combined with nanoscopic plasmonic mode volumes to maximize the system’s photonic performance. Such optimization, however, is difficult in practice because of the inability to easily measure and tune critical system parameters. Here, we present a method to determine the coupling strength and tailor the degree of hybridization in composite optical microresonator-plasmonic nanoparticle systems based on experimentally measured absorption spectra. Specifically, we use thermal annealing to control the detuning between a metal nanoparticle’s localized surface plasmon resonance and the whispering-gallery modes of an optical microresonator cavity. We demonstrate the ability to sculpt Fano resonance lineshapes in the absorption spectrum and infer system parameters critical to elucidating the underlying photonic-plasmonic hybridization. We show that including decoherence processes is necessary to capture the evolution of the lineshapes. As a result, thermal annealing allows us to directly tune the degree of hybridization and various hybrid mode quantities such as the quality factor and mode volume and ultimately maximize the Purcell factor to be 10^4. We will show how a combined photothermal/transmission spectroscopy can allow the fate of all system excitations to be tracked down. Applications of single-particle microresonator spectroscopy to studying conductive polymers and condensed phase dynamics will be discussed if time permits.

This talk was presented by Prof. Randall H. Goldsmith (University of Wisconsin Madison) on August 12, 2020.

Join the Polariton Chemistry Online Community on Facebook:
  / 1000000057118095  

Subscribe to our channel:
   / @polaritonchemistrywebinars100