The use of Liquid Crystal (LC) materials, mainly in display applications, has contributed to major advancement in liquid crystal science and technology. New and more complex phases of liquid crystals were developed to compete with conventional nematic LC displays. The challenge now is to manufacture high birefringence liquid crystal materials with low viscosity. LC is also used in many other applications, such as temperature sensors and photonics beam shaping in the form of spatial light modulators (SLM) and q-plates. The first objective of this thesis is to investigate the magic mirror effect using a SLM following Sir Michael Berry’s theory. Here, we demonstrated a simple way of producing the magic mirror effect using LC devices and aimed to use a micron-sized device to shape the phase and polarization of light with gentle phase variation. We were able to generate the magic mirror image intensity pattern, both experimentally and theoretically. This was done by computing and generating the desired phase pattern of an image on the SLM, then aligning light propagation through this phase pattern. The experimental and theoretical results showed good agreement when comparing the produced intensity patterns. In the second part of this thesis, we experimentally investigated the use of structured photons, created using q-plates, which is a birefringent liquid crystal cell of OAM and SAM coupling, in quantum key distribution (QKD) using the BB84 protocol through orbital angular momentum (OAM) maintaining optical fibres. Here, we were successful in generating a secure key between two parties with a quantum bit error rate of 8.6% which is below the security threshold of 11%. This work demonstrates the feasibility of using structured light in QKD through fibres to boost key rates and security.

Made available in DSpace on 2016-08-10T11:07:20Z (GMT). No. of bitstreams: 1 JOANEDE APARECIDA XAVIER DE SOUZA FE.pdf: 827799 bytes, checksum: 02cfaa63df3aa48cf2381c6c3109fee0 (MD5) Previous issue date: 2014-10-23 / This study aims to analyze the works and The Sorcerer s Apprentice Magic Mirror to present Mario Quintana as a sorcerer s apprentice magician able to transform images into concepts and everyday life in language. The intention in this work is to reveal the poetic to Mario Quintana, seeking to understand and explain how the poet manipulates the imagery of incitement and as evidenced by his poetic concepts. To this end, the work The Anthropological Structures of the Imaginary (2001), and the imaginary, of Gilbert Durand (1994), will provide the theoretical basis and the poetics of reverie, of Gaston Bachelard (2009). Therefore, consider the style and the plurality of styles in Quintana, making a foray into the poetic to prove that the author is not attached to any literary style, though, has it left contaminated by the surreal beauty as a means to seek the freedom of creation, escaping the limitations imposed by so-called literary schools, because the author walked against material society. Thus, his poems explore dreams, fantasies, visions and hallucinations. This dissertational work will be guided by a simple language, even in the case of the theories explored here, since another goal that will guide is to make it work in a research material for teachers and high school students. Therefore, the didactic character will be a goal to be achieved at the end. Thus, it is expected to instigate the reader of this work to pursue the work of Mario Quintana and her make object pleasant and constant reading. / Este estudo objetiva analisar as obras O Aprendiz de Feiticeiro e Espelho Mágico para apresentar Mario Quintana como um feiticeiro aprendiz de mágico capaz de transformar imagens em conceitos e o cotidiano em linguagem. A pretensão nesse trabalho é desvendar o fazer poético de Mário Quintana, buscando entender e explicitar a forma como o poeta manipula a incitação do imaginário e como evidencia seus conceitos poéticos. Para atingir essa finalidade, as obras As estruturas Antropológicas do Imaginário (2001), e O imaginário, de Gilbert Durand (1994), servirão de aporte teórico, bem como A poética do devaneio, de Gaston Bachelard (2009). Para tanto, consideraremos o estilo e a pluralidade de estilos em Quintana, fazendo uma incursão pelo poético para comprovar que o autor não se prendeu a nenhum estilo literário, muito embora, tenha se deixado contaminar pela beleza surreal como meio de buscar a liberdade da criação, fugindo das limitações impostas pelas chamadas escolas literárias, pois o autor caminhou na contramão da sociedade material. Assim, seus poemas exploram sonhos, fantasias, visões e alucinações. Este trabalho dissertativo será pautado por uma linguagem simples, mesmo em se tratando das teorias aqui exploradas, uma vez que outro objetivo que o norteará é fazer com que resulte num material de pesquisa para professores e estudantes do Ensino Médio. Para tanto, o caráter didático será uma meta a ser conquistada ao final. Dessa forma, espera-se instigar o leitor desta dissertação a buscar a obra de Mario Quintana e dela fazer objeto de leitura prazerosa e constante.

Every second, major companies such as Google, Apple, Amazon and Microsoft are col- lecting a great amount of data from users. Photos, voice and texts etc. are stored in the companies massive server parks. With this amount of data, along with technical benefits such as computing power and exceeding algorithms, the companies can train their ma- chine learning models to levels which is hard for a local computing landscape to reach up to.Nowadays, the companies allow developers to use their services and this paper proclaims the benefits of using these. The aim for this thesis is to show how cloud based face recognition and speech recognition can be utilized to create a virtual assistant in Magic Mirror. This new concept opens new possibilities for human-computer interaction.The use case for the assistant was to aid visitors who comes into an office for an appointment with an employee. The prototype of the assistant showed 94% accuracy when identifying faces and fulfilled the task well when the employee name was internationally known, while having difficulties with others, e.g. Swedish names.