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O incessante aumento do volume de informações produzido por uma sociedade cada vez mais informatizada tem elevado drasticamente os requisitos quanto ao desenvolvimento de dispositivos capazes de suportar velocidades de operação cada vez mais elevadas em tamanhos cada vez mais reduzidos. No entanto, a contínua redução do tamanho desses dispositivos, celebrado através da lei de Moore, também produz um indesejável aumento na produção de calor durante a operação dos mesmos, comprometendo seu desempenho global. Uma alternativa promissora para aliviar, ou mesmo superar, estas limitações é oferecida pelos dispositivos ópticos integrados. No entanto, todo esse avanço esbarrava no fato de que as dimensões de tais dispositivos estavam restringidas fundamentalmente ao que é largamente conhecido como limite de difração (LD). Uma maneira de contornar essa limitação é obtida através da utilização de Plásmon Poláritons de Superfície, ou SPPs, que, de maneira simplificada, são ondas que se propagam ao longo da superfície de um condutor depositado sobre um dielétrico. Estas são essencialmente ondas de luz que são localizadas na superfície por causa de sua interação com os elétrons livres do condutor. Nesta interação, os elétrons livres respondem coletivamente oscilando em ressonância com a onda de luz. No presente trabalho, o fenômeno de geração de SPPs é estudado teoricamente e aplicado na modelagem de diversas estruturas de interesse científico e tecnológico, tais como acopladores direcionais e ressoadores. O objetivo principal é a obtenção de estruturas capazes de proporcionar propagação de SPPs por longas distâncias, permitindo, assim, estender ainda mais o leque de possíveis aplicações. As estruturas são investigadas prioritariamente no COMSOL Multiphysics, um aplicativo baseado em elementos finitos que permite solução vetorial de problemas eletromagnéticos. Os resultados obtidos até o momento permitem afirmar que o conceito de SPP de longa distância (long range SPP, LRSPP) podem ser aplicados com sucesso a estruturas geometricamente complexas como os ressoadores em anel e acopladores direcionais. / The continuous growth of knowledge produced by a society with increasing access to information technologies has demanded the development of communication devices capable of supporting high processing speeds at more and more reduced sizes. Nevertheless, the continuous reduction of the size of these devices, celebrated by the Moore\'s law, has also produced an undesirable increase of heat produced during the operation of the device itself, compromising its overall performance. A promising alternative to alleviate, or even overcome, these limitations has been offered by photonic integrated circuits. However, all the advance of photonic devices was restricted to what is known as diffraction limit. A fascinating way of circumventing this limit is now available to the scientific community, and consists in the generation of Surface Plasmon Polariton (SPP) waves. In a simplified manner, SPP waves are waves that propagate along a metal/dielectric interface. These waves are essentially localized at the metal/dielectric interface because of the interaction of light with free electrons of the metal. In this interaction, the free electrons respond collectively and oscillate resonantly with the incident light. In the present work, the phenomenon of SPP generation is theoretically investigated and applied to the modeling of several structures, such as directional couplers and resonators. The primary goal of this work is to design structures capable propagating SPP waves for long distances, known as long range SPP (LRSPP). The structures are investigated mostly with COMSOL Multiphysics, a finite elements based software that allows for the vectorial solution of electromagnetic problems. The results obtained so far are extremely encouraging, and prove that the LRSPP concept can be successfully applied to geometrically complex structures, such as couplers and ring resonators.

We investigate the propagation of light in different conditions that lead to exotic propagation of photons and use near-resonant light-matter interactions to enhance these effects. First, we study the propagation of light in a moving highly dispersive medium, namely rubidium atoms. Based on the special relativity the speed of light changes with the speed of the medium. However, this drag effect in a non-dispersive medium is very small and thus difficult to measure. We show that the drag effect is enhanced significantly when the moving medium is highly dispersive. Thus, with this enhancement even a slow motion can be detected. Next, we employ the large nonlinear response of rubidium atoms to accentuate the formation of optical caustics. Caustics are important as nature uses caustics to concentrate the energy of waves. Moreover, caustics can be formed in many physical systems such as water waves in oceans to amplify tsunamis or generate rogue waves. The connection of our study to these giant water waves is discussed. Finally, we explore light-matter interactions in plasmonic systems. We show that photons experience a significant phase jump as they couple into and out of a plasmonic structure. This coupling phase, also known as the scattering phase shift, is generic to all scattering events. We measure this coupling phase with a triple-slit plasmonic structure. Moreover, we use the near-field enhancement of the plasmonic structure to enhance the coupling between the slits. Consequently, the photons can take non-trivial trajectories that pass through all three slits. We measure such exotic trajectories for the first time that are seemingly in violation of the superposition principle. The application of the superposition principle and the validity of Born’s rule is discussed.

A novel process for the fabrication of Long Range Surface Plasmon Polariton (LRSPP) waveguide based biosensors is presented herein. The structure of the biosensor is comprised of Au stripe waveguide devices embedded in thick CYTOP claddings with a SiO2 solvent diffusion barrier and etch-stop layer. The SiO2 layer is introduced to improve the end quality of Au waveguide structures, which previously deformed during the deposit of the upper cladding process and to limit the over-etching of CYTOP to create micro-fluidic channels. The E-beam evaporation method is adapted to deposit a thin SiO2 on the bottom cladding of CYTOP. A new micro-fluidic design pattern is introduced. Micro-fluidic channels were created on selective Au waveguides through O2 plasma etching. The presented data and figures are refractive index measurements of different materials, thickness measurements, microscope images, and AFM images. Optical power cutback measurements were performed on fully CYTOP-cladded symmetric LRSPP waveguides. The end-fire coupling method was used to excite LRSPP modes with cleaved polarization maintaining (PM) fibre. The measured mode power attenuation (MPA) was 6.7 dB/mm after using index-matched liquid at input and output fibre-waveguide interfaces. The results were compared with the theoretical calculations and simulations. Poor coupling efficiency and scattering due to the SiO2 are suspected for off-target measurements.

A novel process for the fabrication of Long Range Surface Plasmon Polariton (LRSPP) waveguide based biosensors is presented herein. The structure of the biosensor is comprised of Au stripe waveguide devices embedded in thick CYTOP claddings with a SiO2 solvent diffusion barrier and etch-stop layer. The SiO2 layer is introduced to improve the end quality of Au waveguide structures, which previously deformed during the deposit of the upper cladding process and to limit the over-etching of CYTOP to create micro-fluidic channels. The E-beam evaporation method is adapted to deposit a thin SiO2 on the bottom cladding of CYTOP. A new micro-fluidic design pattern is introduced. Micro-fluidic channels were created on selective Au waveguides through O2 plasma etching. The presented data and figures are refractive index measurements of different materials, thickness measurements, microscope images, and AFM images. Optical power cutback measurements were performed on fully CYTOP-cladded symmetric LRSPP waveguides. The end-fire coupling method was used to excite LRSPP modes with cleaved polarization maintaining (PM) fibre. The measured mode power attenuation (MPA) was 6.7 dB/mm after using index-matched liquid at input and output fibre-waveguide interfaces. The results were compared with the theoretical calculations and simulations. Poor coupling efficiency and scattering due to the SiO2 are suspected for off-target measurements.

A novel process for the fabrication of Long Range Surface Plasmon Polariton (LRSPP) waveguide based biosensors is presented herein. The structure of the biosensor is comprised of Au stripe waveguide devices embedded in thick CYTOP claddings with a SiO2 solvent diffusion barrier and etch-stop layer. The SiO2 layer is introduced to improve the end quality of Au waveguide structures, which previously deformed during the deposit of the upper cladding process and to limit the over-etching of CYTOP to create micro-fluidic channels. The E-beam evaporation method is adapted to deposit a thin SiO2 on the bottom cladding of CYTOP. A new micro-fluidic design pattern is introduced. Micro-fluidic channels were created on selective Au waveguides through O2 plasma etching. The presented data and figures are refractive index measurements of different materials, thickness measurements, microscope images, and AFM images. Optical power cutback measurements were performed on fully CYTOP-cladded symmetric LRSPP waveguides. The end-fire coupling method was used to excite LRSPP modes with cleaved polarization maintaining (PM) fibre. The measured mode power attenuation (MPA) was 6.7 dB/mm after using index-matched liquid at input and output fibre-waveguide interfaces. The results were compared with the theoretical calculations and simulations. Poor coupling efficiency and scattering due to the SiO2 are suspected for off-target measurements.

O incessante aumento do volume de informações produzido por uma sociedade cada vez mais informatizada tem elevado drasticamente os requisitos quanto ao desenvolvimento de dispositivos capazes de suportar velocidades de operação cada vez mais elevadas em tamanhos cada vez mais reduzidos. No entanto, a contínua redução do tamanho desses dispositivos, celebrado através da lei de Moore, também produz um indesejável aumento na produção de calor durante a operação dos mesmos, comprometendo seu desempenho global. Uma alternativa promissora para aliviar, ou mesmo superar, estas limitações é oferecida pelos dispositivos ópticos integrados. No entanto, todo esse avanço esbarrava no fato de que as dimensões de tais dispositivos estavam restringidas fundamentalmente ao que é largamente conhecido como limite de difração (LD). Uma maneira de contornar essa limitação é obtida através da utilização de Plásmon Poláritons de Superfície, ou SPPs, que, de maneira simplificada, são ondas que se propagam ao longo da superfície de um condutor depositado sobre um dielétrico. Estas são essencialmente ondas de luz que são localizadas na superfície por causa de sua interação com os elétrons livres do condutor. Nesta interação, os elétrons livres respondem coletivamente oscilando em ressonância com a onda de luz. No presente trabalho, o fenômeno de geração de SPPs é estudado teoricamente e aplicado na modelagem de diversas estruturas de interesse científico e tecnológico, tais como acopladores direcionais e ressoadores. O objetivo principal é a obtenção de estruturas capazes de proporcionar propagação de SPPs por longas distâncias, permitindo, assim, estender ainda mais o leque de possíveis aplicações. As estruturas são investigadas prioritariamente no COMSOL Multiphysics, um aplicativo baseado em elementos finitos que permite solução vetorial de problemas eletromagnéticos. Os resultados obtidos até o momento permitem afirmar que o conceito de SPP de longa distância (long range SPP, LRSPP) podem ser aplicados com sucesso a estruturas geometricamente complexas como os ressoadores em anel e acopladores direcionais. / The continuous growth of knowledge produced by a society with increasing access to information technologies has demanded the development of communication devices capable of supporting high processing speeds at more and more reduced sizes. Nevertheless, the continuous reduction of the size of these devices, celebrated by the Moore\'s law, has also produced an undesirable increase of heat produced during the operation of the device itself, compromising its overall performance. A promising alternative to alleviate, or even overcome, these limitations has been offered by photonic integrated circuits. However, all the advance of photonic devices was restricted to what is known as diffraction limit. A fascinating way of circumventing this limit is now available to the scientific community, and consists in the generation of Surface Plasmon Polariton (SPP) waves. In a simplified manner, SPP waves are waves that propagate along a metal/dielectric interface. These waves are essentially localized at the metal/dielectric interface because of the interaction of light with free electrons of the metal. In this interaction, the free electrons respond collectively and oscillate resonantly with the incident light. In the present work, the phenomenon of SPP generation is theoretically investigated and applied to the modeling of several structures, such as directional couplers and resonators. The primary goal of this work is to design structures capable propagating SPP waves for long distances, known as long range SPP (LRSPP). The structures are investigated mostly with COMSOL Multiphysics, a finite elements based software that allows for the vectorial solution of electromagnetic problems. The results obtained so far are extremely encouraging, and prove that the LRSPP concept can be successfully applied to geometrically complex structures, such as couplers and ring resonators.

This report examines the cross sections of silver microresonators subjected to an incident light with different polarization. The microresonators had different geometries with and without broken symmetries. Cross section profiles for different microresonator configurations are interesting for the division of Material Physics, Uppsala University, when designing metamaterials to tune the optical response of the material. The goal is to form an insight of how the optical response can be tuned by choosing different geometries, varying the size and polarization of the incident light. In this project computer simulations in COMSOL were made to simulate the optical response of different microresonators. When the incident light interact with the silver microresonators plasmonic excitations is generated which in turn interacts with the light changing the phase and therefore the optical response. By increasing the radius of the disk silver microresonantors the resonance was found to shift to lower energies. For a geometry with a disk microresonator inside a ring microresonator the Fano resonances were dependent of the radius of the disk microresonator.

A novel process for the fabrication of Long Range Surface Plasmon Polariton (LRSPP) waveguide based biosensors is presented herein. The structure of the biosensor is comprised of Au stripe waveguide devices embedded in thick CYTOP claddings with a SiO2 solvent diffusion barrier and etch-stop layer. The SiO2 layer is introduced to improve the end quality of Au waveguide structures, which previously deformed during the deposit of the upper cladding process and to limit the over-etching of CYTOP to create micro-fluidic channels. The E-beam evaporation method is adapted to deposit a thin SiO2 on the bottom cladding of CYTOP. A new micro-fluidic design pattern is introduced. Micro-fluidic channels were created on selective Au waveguides through O2 plasma etching. The presented data and figures are refractive index measurements of different materials, thickness measurements, microscope images, and AFM images. Optical power cutback measurements were performed on fully CYTOP-cladded symmetric LRSPP waveguides. The end-fire coupling method was used to excite LRSPP modes with cleaved polarization maintaining (PM) fibre. The measured mode power attenuation (MPA) was 6.7 dB/mm after using index-matched liquid at input and output fibre-waveguide interfaces. The results were compared with the theoretical calculations and simulations. Poor coupling efficiency and scattering due to the SiO2 are suspected for off-target measurements.