Surface plasmons¡]SPs¡^have been extensive applied to various kinds of detector and devices. There are very great relations of physical quantity, such as resonant angle, damping rate, halfwidth of resonance and reflection rate, etc. of resonating in the exciting of SPs. In this study, we derived some approximate formulas of these physical quantities from fresnel¡¦s formulas and pole approximate expansion, such as, the damping rate of SPs, the resonant angle, the optimum metallic thickness of these structure. In addition, we have also proceeding to some numerical simulations. Surface plasmons can also apply to near-field optics, using the super-resolution near-field structure¡]Super-RENS¡^ , the data densities can be promoted, and the diffraction limit can be overcome. SPs are excited at the Sb/SiN interface may concentrate light spot and enhance the field intensity. In this study, we have also expounded the fact that its antimony film in a Super-RENS of propagation, function and simulation of the SPs. As a result of calculations and simulations, we conclude that the enhanced filed intensity is larger for a system using a metal with a smaller imaginary part of the dielectric constant. The resonant angle decreases when the dielectric constant of the prism increases and the dielectric constant of the intermediate layer decreases. In addition, the optimum resonant condition in Super-RENS can be made by proper selection of parameters.

Tailoring surface plasmon (SP) resonances using metallic nanostructures for optical manipulation has been widely investigated in recent years; and there are many puzzles yet to be solved in this relatively new area. This thesis covers the study of the interaction of light with SP-supporting planar/patterned metallo-dielectric multilayer structures. Two separate, but closely related subjects were investigated using such structures, which are: SP-assisted optical transmission and optical metamaterials. The physical mechanisms of the SP-assisted transmission phenomenon were studied using planar/grating and planar/hole-array multilayer structures. Extraordinary light transmission has been demonstrated through experimental work and simulations for both arrangements; and the effects of different structural parameters on the transmission efficiencies of the structures were analyzed systematically. The interplays of the surface plasmon polaritons (SPPs) and localized surface plasmons (LSPs) in the extraordinary optical transmission (EOT) phenomenon were identified. The potential of the planar/hole-array multilayer structures as optical magnetic metamaterials was evaluated using two independent electromagnetic simulation techniques. The ability of such structures to produce strong magnetic resonances from infrared down to visible side of spectrum was revealed. The methods of tuning the magnetic response of the structures were suggested. A novel design of optical metamaterial based on high-order multipolar resonances in a single-layer plasmonic structure was also proposed. Numerical results from two different computation methods indicate that a simultaneously negative permittivity and permeability can be achieved in such a structure.

At the interface between a metal and dielectric, it is possible for an electromagnetic wave to couple with the conduction electrons of the metal to create a coupled oscillation known as a surface plasmon. These surface plasmons can exhibit properties which are not shared with their purely electronic or electromagnetic components. Such unique properties include the ability to transmit plasmonic waves through sub-wavelength spaces, opening up the possibility of combining the high data density seen in photonics-based information technologies with the nanometer-scale electronic components of modern integrated circuitry. Other plasmon properties such as the highly resonant nature of plasmon excitation may potentially lend themselves to novel cancer treatments and medical probing techniques. In order to develop such technologies, a deeper understanding of surface plasmons and their relationship with a material’s properties and structure is necessary. In the present work, angle- and energy-resolved optical measurements for a square lattice of circular Fe20Pd80 islands are presented in the form of reflectivity and transmission maps, along with higher resolution reflectivity, transmission, and TMOKE measurements for a few specific wavelengths. A theoretical model describing the connection between plasmonic and magneto-optical behavior is described and compared with the experimental data, showing a very high correlation.

This thesis describes work carried out on the research, development and implementation of new processes for the fabrication of surface plasmon waveguide biosensors. Fabrication of surface plasmon resonance (SPR) based waveguides embedded in a thick CYTOP cladding with the incorporation of fluidic channels was achieved with improved quality and operability compared to previous attempts. The fabrication flow was modified in key areas including lithography for feature definition, gold evaporation and the upper cladding deposition procedure. The combined result yielded devices with sharper resolution of waveguides, gold surfaces with minimal aberrations, reduced surface roughness and minimization of waveguide deformation due to reduction of solvent diffusion into the lower cladding. The fabricated waveguides consisted of a thin, 35 nm, patterned gold film, embedded in a thick, 18 µm, CYTOP fluoroploymer cladding. The gold devices were exposed by O2 plasma etching through the upper cladding to form fluidic channels for the facilitation of flow of an index matched sensing medium. Optical and physical characterization of devices revealed structures of significantly improved quality over previous attempts, rendering the platform competitive for biosensing applications.

This thesis describes work carried out on the research, development and implementation of new processes for the fabrication of surface plasmon waveguide biosensors. Fabrication of surface plasmon resonance (SPR) based waveguides embedded in a thick CYTOP cladding with the incorporation of fluidic channels was achieved with improved quality and operability compared to previous attempts. The fabrication flow was modified in key areas including lithography for feature definition, gold evaporation and the upper cladding deposition procedure. The combined result yielded devices with sharper resolution of waveguides, gold surfaces with minimal aberrations, reduced surface roughness and minimization of waveguide deformation due to reduction of solvent diffusion into the lower cladding. The fabricated waveguides consisted of a thin, 35 nm, patterned gold film, embedded in a thick, 18 µm, CYTOP fluoroploymer cladding. The gold devices were exposed by O2 plasma etching through the upper cladding to form fluidic channels for the facilitation of flow of an index matched sensing medium. Optical and physical characterization of devices revealed structures of significantly improved quality over previous attempts, rendering the platform competitive for biosensing applications.

A theoretical treatment is presented of a plasmonic interaction at an interface between a semiconductor and a dielectric, as opposed to the more traditional configuration whereby a metal/dielectric interface is investigated. Our work is to show that structures using semiconductors instead of metal to excite surface plasmon can support not only terahertz frequencies plasmons but also optical frequency (around 10 to power of 15 Hz) plasmons. / Thesis

This thesis describes work carried out on the research, development and implementation of new processes for the fabrication of surface plasmon waveguide biosensors. Fabrication of surface plasmon resonance (SPR) based waveguides embedded in a thick CYTOP cladding with the incorporation of fluidic channels was achieved with improved quality and operability compared to previous attempts. The fabrication flow was modified in key areas including lithography for feature definition, gold evaporation and the upper cladding deposition procedure. The combined result yielded devices with sharper resolution of waveguides, gold surfaces with minimal aberrations, reduced surface roughness and minimization of waveguide deformation due to reduction of solvent diffusion into the lower cladding. The fabricated waveguides consisted of a thin, 35 nm, patterned gold film, embedded in a thick, 18 µm, CYTOP fluoroploymer cladding. The gold devices were exposed by O2 plasma etching through the upper cladding to form fluidic channels for the facilitation of flow of an index matched sensing medium. Optical and physical characterization of devices revealed structures of significantly improved quality over previous attempts, rendering the platform competitive for biosensing applications.

We present a theoretical analysis of surface-plasmon-mediated mode-coupling in a planar thin film metal/insulator stack. The spatial overlap of a surface plasmon polariton (SPP) and a waveguide mode results in a Fano interference analog. Tuning of the material parameters effects the modes and output fields of the system. Lastly, the intensity and phase sensitivity of the system are compared to a standard surface plasmon resonance (SPR). We begin with background information on Fano interference, an interference effect between two indistinguishable pathways. Originally described for autoionization, we discuss the analogs in other systems. We discuss the features of Fano interference in the mode diagrams, and the Fano resonance observed in the output field. The idea of a geometric Fano resonance (GFR) occurring in the angular domain is presented. Background information on surface plasmon polaritons is covered next. The dielectric properties of metals and how they relate to surface plasmons is first reviewed. The theoretical background of SPPs on an infinite planar surface is covered. The modes of a two planar interface metal/insulator stack are reviewed and the leaky properties of the waveguide are shown in the reflectance. We solve for modes of a three interface metal/insulator stack and shows an avoided crossing in the modes indicative of Fano interference. We observe the asymmetric Fano resonance in the angular domain in the reflectance. The tunability of the material parameters tunes the GFR of the system. The GFR tuning is explored and different Fano lineshapes are observed. We also observe a reversal of the asymmetry Fano lineshape, attributed to the relate phase interactions of the non-interacting modes. The phase of the GFR is calculated and discussed for the variations of the parameters. The reflected field is explored as the insulator permittivities are varied. As the waveguide permittivity is varied, we show there is little response from the system. As the exterior permittivity is varied, the reflectance exhibits the geometric Fano resonance and the tunability of the lineshape is explored. Finally, we calculate the sensitivities of our metal/insulator stack to changes in the permittivity and compare them to the sensitivities of SPRs.

In this thesis, the spectral behavior of the fundamental and sum-frequency waves, generated from the surface of a thin metal film in the Kretschmann configuration, is theoretically studied with coherent ultrashort pulses. As a first exploration of considering spectral response in nonlinear plasmonics, it is shown that the spectra of reflected sum-frequency waves exhibit pronounced shifts for the incident fundamental waves close to the plasmon coupling angle, whereas meanwhile those of reflected fundamental waves display energy holes. We also demonstrate that the scale of discovered plasmon-enhanced spectral changes is strongly influenced by the magnitude of the incidentce angle and the source pulse duration, and at a certain angle a spectral switch is observed. The appearance of large sum-frequency wave shifts can serve as an unambiguous plasmon signatur in nonlinear surface spectroscopy. Also, the discovered spectral switch can trigger extremely surface-sensitive nonlinear plasmonic sensors.

Interest in the fabrication of nano-optical structures has increased dramatically in recent years, due to advances in lithographic resolution. In particular, metallic nanostructures are of interest because of their ability to concentrate light to well below the diffraction limit. Such structures have many potential applications, including nanoscale photonics, quantum information processing and single molecule detection/imaging. In the case of quantum computing and quantum communication, plasmon-based metal nanostructures offer the promise of scalable devices. This is because the small optical mode volumes of such structures give the large atom-photon coupling needed to interface solid-state quantum bits (qubits) to photons. The main focus of this dissertation is on fabrication and testing of surface plasmon-based metal nanostructures that can be used as optical wires for effciently collecting and directing an isolated atom or molecule's emission. In this work, Ag waveguides having 100nm£50nm and 50nm£50nm cross sections have been fabricated ranging from 5¹m to 16¹m in length. Different types of coupling structures have also been fabricated to allow in-coupling and out-coupling of free space light into and out of the nanometric waveguides. The design of waveguides and couplers have been accomplished using a commercial finite difference in time domain (FDTD) software. Different nanofabrication techniques and methods have been investigated leading to robust and reliable process conditions suitable for very high aspect ratio fabrication of metal structures. Detailed testing and characterization of the plasmon based metal waveguides and couplers have also been carried out. Test results have revealed effective surface plasmon propagation range. 0.5dB/¹m and 0.07dB/¹m transmission losses have been found for 100nm and 50nm wide waveguides respectively, which correspond to 1/e propagation lengths of 9¹m and 60¹m. Input coupling effciency was found to be 2% and output coupling effciency was found to be 35%. The fabrication and testing results presented provide critical demonstrations to establish the feasibility of nanophotonic integrated circuits, scalable quantum information processing devices, as well as other devices, such as single molecule detectors and imaging systems.