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1	Plasmon Polariton Bragg Gratings and IR-140 Doped PMMA for Active Bragg Structures Amyot-Bourgeois, Maude January 2016 (has links) This thesis contributes to the realisation of plasmonic lasers based on plasmon polariton Bragg gratings. The scope of this thesis is twofold. In the first section, entitled Passive plasmonic Bragg grating characterization, the results of the testing and characterization of a new design of plasmonic Bragg gratings in the near-infrared are presented. The reflection and transmission responses expected from plasmon-polariton Bragg gratings (PPBGs) are treated theoretically using the transfer matrix method (TMM) and the numerical model is validated experimentally. The experimental setup and procedures are then described in detail. Results show that the near-infrared plasmon polariton Bragg gratings possess a Bragg reflection at a wavelength close to the Bragg wavelength predicted by TMM. In the second section, Gain optimisation and bleaching of IR-140 doped PMMA, an in-depth analysis of the gain medium (IR-140 dye doped poly(methyl methacrylate) better known as PMMA) is performed. This gain medium was selected as a gain layer for active plasmonic gratings and distributed feedback lasers designed by a colleague Ph.D. candidate. The optimized molecular weight of IR-140 in PMMA was found to be 0.9% to obtain a material gain of 81 cm-1. plasmonics gain material Bragg gratings
2	Plasmonic properties and applications of metallic nanostructures Zhen, Yurong 16 September 2013 (has links) Plasmonic properties and the related novel applications are studied on various types of metallic nano-structures in one, two, or three dimensions. For 1D nanostructure, the motion of free electrons in a metal-film with nanoscale thickness is confined in its normal dimension and free in the other two. Describing the free-electron motion at metal-dielectric surfaces, surface plasmon polariton (SPP) is an elementary excitation of such motions and is well known. When further perforated with periodic array of holes, periodicity will introduce degeneracy, incur energy-level splitting, and facilitate the coupling between free-space photon and SPP. We applied this concept to achieve a plasmonic perfect absorber. The experimentally observed reflection dip splitting is qualitatively explained by a perturbation theory based on the above concept. If confined in 2D, the nanostructures become nanowires that intrigue a broad range of research interests. We performed various studies on the resonance and propagation of metal nanowires with different materials, cross-sectional shapes and form factors, in passive or active medium, in support of corresponding experimental works. Finite- Difference Time-Domain (FDTD) simulations show that simulated results agrees well with experiments and makes fundamental mode analysis possible. Confined in 3D, the electron motions in a single metal nanoparticle (NP) leads to localized surface plasmon resonance (LSPR) that enables another novel and important application: plasmon-heating. By exciting the LSPR of a gold particle embedded in liquid, the excited plasmon will decay into heat in the particle and will heat up the surrounding liquid eventually. With sufficient exciting optical intensity, the heat transfer from NP to liquid will undergo an explosive process and make a vapor envelop: nanobubble. We characterized the size, pressure and temperature of the nanobubble by a simple model relying on Mie calculations and continuous medium assumption. A novel effective medium method is also developed to replace the role of Mie calculations. The characterized temperature is in excellent agreement with that by Raman scattering. If fabricated in an ordered cluster, NPs exhibit double-resonance features and the double Fano-resonant structure is demonstrated to most enhance the four-wave mixing efficiency. light harvesting perfect absorber surface plasmon polariton periodic hole array dispersion relation Brillouin zone degenerate perturbation splitting nanofilm nanobelt subwavelength cross section localized surface plasmon resonance LSPR redshift with aspect ratio nanowire mode area confinement propagation length Figure of Merit nanophotonics waveguide stimulated emission of surface plasmon gain material loss compensation nanoscale heat transfer nanobubble Mie calculation effective medium near field weighting mean field theory Fano resonance four-wave mixing nanocluster nanodisk coherent nonlinear optics

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Plasmon Polariton Bragg Gratings and IR-140 Doped PMMA for Active Bragg Structures

Plasmonic properties and applications of metallic nanostructures