Hybrid Systems of Plasmonic Nanostructures and Functional Materials for Light-matter Interactions and Active Plasmonic Devices

Download or read book Hybrid Systems of Plasmonic Nanostructures and Functional Materials for Light-matter Interactions and Active Plasmonic Devices written by Mingson Wang (Ph. D.) and published by . This book was released on 2018 with total page 346 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in nanofabrication and characterization of nanomaterials enable the development of plasmonic nanostructures with unique optical properties. Plasmonic nanostructures have been extensively studied for their potential applications in optical sensing, photothermal therapy, photovoltaics, and photocatalysis. In this dissertation, we present studies of light-matter interactions in hybrid systems consisting of plasmonic nanostructures and functional materials. These studies are focused on four major types of light-matter interactions in plasmonic nanostructures: (1) plasmon-induced resonance energy transfer (PIRET); (2) plasmon-enhanced spontaneous emission; (3) Fano interference between plasmonic nanostructures and emitters; and (4) strong plasmon-exciton coupling. We also achieved the tuning of light-matter interactions by modifying the physical properties of functional materials or plasmonic nanostructures. In addition, the active control of light-matter interactions was demonstrated by integrating plasmonic nanostructures with switchable materials, such as photochromic dyes. Specifically, we first demonstrated the blue-shifted PIRET from a single gold nanorod (AuNR) to dye molecules. AuNRs enable the energy transfer from plasmonic donors to dye acceptors with light having a longer wavelength and lower intensity, compared to dye donors. Secondly, we studied the tuning of plasmon-trion and plasmon-exciton resonance energy transfer from a single gold nanotriangle (AuNT) to monolayer MoS2. We achieved these phenomena by the combination of rationally designed monolayer MoS2-plasmonic nanoparticle hybrid systems and single-nanoparticle measurements. Thirdly, we realized the large modulation of hybrid plasmonic waveguide mode (HPWM) in single hybrid molecule-plasmon nanostructures through the strong molecule-plasmon coupling. The HPWM features both the capacity of plasmonic nanostructures to manipulate light at the nanoscale and the low loss of dielectric waveguides. Fourthly, we demonstrated the photoswitchable plasmon-induced fluorescence enhancement. This large switchable modulation of fluorescence was derived from the large near-field enhancement at the subnanometer gap between Au nanoparticles and switchable intersystem crossing as a nonradiative decay channel in photochromic dyes. Finally, we achieved tunable Fano resonances and plasmon-exciton coupling in two-dimensional (2D) WS2-AuNT hybrid structures at room temperature. The tuning of Fano resonances and plasmon-exciton coupling were achieved by the active control of the WS2 exciton binding energy and dipole-dipole interaction through controlling the dielectric constant of the surrounding medium.