| Surface Plasmon Polaritons (SPP) are surface modes that propagate at metal-dielectric interfaces and constitute an electromagnetic field coupled to oscillations of the conduction electrons at the metal surface. The fields associated with the SPP are enhanced at the surface and decay exponentially into the media on either side of the interface. Recently, it was proposed that plasmonic structures and devices operating in the optical domain offer advantages for applications such as on-chip integration of optical circuits, data storages, and bio-sensing. By varying the surface nanotopology, the optical properties of SPPs can be tailored via so-called Surface Dispersion Engineering.;This thesis is largely focused on the development of plasmonic components on a chip using surface dispersion engineering technology, including systematic investigations on (1) coupling, (2) waveguiding, (3) manipulation and (4) application of engineered SPP modes. More specifically, in Chapter 2, novel SPP coupling mechanisms will be investigated. Compared with the bulky conventional SPR coupling mechanism, nanopatterns are employed as miniaturized plasmonic surface wave couplers to couple the light to SPP modes.;In Chapter 3, nanopatterned metallic surface are employed for waveguiding. By properly designing the geometric parameters of the structures, surface bandgaps can be created to realize a novel bidirectional surface wave splitter.;In Chapter 4, the slow-light properties of SPP modes supported by the nanopatterned surfaces will be investigated. Using a graded grating structure, multi-wavelengths could be slow down and trapped at different positions along the metal surface, which is so called "rainbow" trapping effect.;In Chapter 5, the structures investigated in the previous chapters are combined to design a novel plasmonic sensing architecture, e.g. vertical plasmonic Mach-Zehnder Interferometer. Such a novel integrated biosensing platform is promising for miniaturized, low cost, sensitive and label-free biosensing applications.;The objective of this thesis is to construct a new framework to describe the propagation, diffraction and interference of SPPs on-a-chip, and develop plasmonic integrated circuits with novel or improved functionalities. |
