Nordlander, Peter2019-05-162019-05-162017-082017-08-10August 201Yang, Xiao. "Extraordinary light-induced local field, angular momentum and force near metallic nanoparticles." (2017) Diss., Rice University. <a href="https://hdl.handle.net/1911/105493">https://hdl.handle.net/1911/105493</a>.https://hdl.handle.net/1911/105493The intense local field induced near metallic nanostructures provides strong enhancements for surface enhanced spectroscopies, a major focus of plasmonics research over the past decade. Here we show several different nanoantennas for SEIRA detection, which exhibit an order of magnitude greater SEIRA sensitivity than previous record-setting designs. We also consider that plasmonic nanoparticles can induce remarkably large electromagnetic field gradients near their surfaces, which can excite dipole-forbidden transitions in nearby atoms or molecules and provide unique spectroscopic fingerprinting for chemical and bimolecular sensing. We introduce the concept of the local angular momentum (LAM) vector as a useful figure of merit for the design of nanostructures that provide large field gradients. Finally, we introduce a new technique that can demonstrate the mapping of electromagnetic forces between a nanoscale tip and an optically excited sample consisting of plasmonic nanostructures with an imaging platform based on atomic force microscopy.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.SEIRALocal Angular MomentumPiFMThesis2019-05-16