Controlling the flow of light at the nanoscale is fundamental to optical applications. Plasmonics, the sub-wavelength surface electromagnetic waves that are guided on a metal-dielectric interface, enable a promising approach for achieving the downscaling of light due to its extreme light confinement. However, current plasmonic structures encounter significant limitations due to (1) high optical losses and (2) the lack of efficient tunability. In this talk, I will present the use of alternative low-loss plasmonic materials, i.e., transparent conducting oxides, to actively control the optical properties of plasmonic and metasurface structures, allowing us to study the fundamental nature of light-matter interactions and apply it to emergent optical phenomena of novel optical applications.
I will first present the use of tunable low-loss active materials, transparent conducting oxides, to demonstrate an efficient plasmonic modulation that operates via solid-state MOS field-effect dynamics , and an electrically driven plasmonic resonant structure that can tune the optical dispersion . I will then discuss the integration of very different but remarkably sciences, plasmonics and photonic crystal fiber optics, for the development of a new class of hybrid plasmonic/photonic waveguides. Such hybrid "nanostructured"-fibers provide a promising unique platform with controllable optical dispersion and long interaction lengths for the investigation of plasmonic/metamaterial optical properties and the realization of novel in-fiber applications [3, 4]. Finally, I will discuss the advantages of integrating conducting oxides with metallic nanoantenna to develop tunable metasurfaces for next-generation nano-optical components, such as ultrathin tunable optical lenses, beam steering or spectral splitting elements.