Nordlander, PeterHalas, Naomi2017-08-012017-11-012017-052016-12-16May 2017Cui, Yao. "Molecular Plasmonics." (2016) Diss., Rice University. <a href="https://hdl.handle.net/1911/96007">https://hdl.handle.net/1911/96007</a>.https://hdl.handle.net/1911/96007Graphene supports surface plasmons that have been observed to be both electrically and geometrically tunable in the midto far-infrared spectral regions. In particular, it has been demonstrated that graphene plasmons can be tuned across a wide spectral range spanning from the mid-infrared to the terahertz. The identification of a general class of plasmonic excitations in systems containing only a few dozen atoms permits us to extend this versatility into the visible and ultraviolet. As appealing as this extension might be for active nanoscale manipulation of visible light, its realization constitutes a formidable technical challenge. We experimentally demonstrate the existence of molecular plasmon resonances in the visible for ionized polycyclic aromatic hydrocarbons (PAHs), which we reversibly switch by adding, then removing, a single electron from the molecule. The charged PAHs display intense absorption in the visible regime with electrical and geometrical tunability analogous to the plasmonic resonances of much larger nanographene systems. Finally, we also use the switchable molecular plasmon in PAHs to demonstrate a proof-of-concept low-voltage electrochromic device.application/pdfengCopyright is held by the author, unless otherwise indicated. Permission to reuse, publish, or reproduce the work beyond the bounds of fair use or other exemptions to copyright law must be obtained from the copyright holder.Plasmonicspolycyclic aromatic hydrocarbonsphotonicsgrapheneplasmon-phonon couplingThesis2017-08-01