Directional Optical Antennas, Wafer-Scale Metasurfaces, and Single Molecule Surface-Enhanced Raman Scattering

Abstract

Within the field of optics, one of the topics being currently investigated with considerable interest is that of plasmonics, which refers to the use of surface plasmons on metallic nanostructures to manipulate light. It can be argued that this has been largely driven by two reasons. First, surface plasmons enable light to be concentrated into deep sub-wavelength regions, and therefore provide a means for overcoming the diffraction limit, which states that light can be focused to dimensions no smaller than roughly half the wavelength. Second, recent years have seen rapid development in nanofabrication methods - largely driven by applications in silicon microelectronics - that permit the realization of the metallic nanostructures needed for plasmonics. The goal of this thesis has been to harness these recent dramatic advances in plasmonics to address a long-standing problem in optics: the fact that Raman scattering cross sections are very small.