Hot-carriers and losses in plasmonic nanostructures

Thomas Brick, Engineering And Physical Sciences Research Council, Cortés Emiliano, Stefan Maier
2019
Despite the remarkable achievements that plasmonics has provided to the field of nanotechnology over the past few decades, we are now faced with the uncomfortable notion that losses associated with plasmonic excitations are limiting the field's full theorised potential. This work addresses the source of these limitations and – rather than avoid – seeks to provide methods that utilise these losses. Plasmonic decay leads to the production of hot charge carriers, that is, electrons and holes with
more » ... ons and holes with energies notably greater than that of electrons at the Fermi level. Electron-electron scattering following production of such hotcarriers precedes temperature increases in the plasmon-supporting nanostructures. This thesis, in part, addresses this mechanism of heating in the context of plasmonic optical printing. Using computational simulations of both the temperature profile in and around an illuminated plasmonic nanoparticle and the resultant fluid velocity field in the surrounding media, we address the previously unresolved experimental issues surrounding inaccuracies in printing dense arrays of plasmonic nanoparticles. This thesis also considers the extraction of these energetic hot-carriers, particularly in the context of plasmonic catalysis. A study into the use of hotelectrons following plasmonic decay in colloidal silver nanoparticles is presented, with a focus on their role in the oxidation of a non-fluorescent molecule into a fluorescent product. We then turn to consider the use of this plasmon-decay induced reaction in super-resolution experiments, with a view to unravelling the energetics and the spatial formation of hot-carriers following plasmon decay.
doi:10.25560/70712 fatcat:fufpayjghjdzhb5fqhrylsvrai