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Complementarity and uncertainty in quantum interferenceShilladay, Christopher Robin January 2007 (has links)
This thesis is concerned with the notions of complementarity and uncertainty encountered in quantum mechanics. Its starting point is an assessment of how these concepts have been represented and illustrated by various writers dating back to their inception. Following the survey a coherent account of the connections and contrasts between complementarity and uncertainty is developed in the context of Mach-Zehnder interferometry. The effect on the interference pattern contrast of path detection via entanglement with a probe system, is explored and a joint unsharp measurement scheme of the complementary pairs, path and interference, described. The Mach-Zehnder set-up proves sufficiently versatile to show that quantum erasure and quantitative quantum erasure constitute instances of joint unsharp measurement of complementary observables. The analysis uses the representation of observables as positive operator valued measures. Path detection and interference observation require different experimental set-ups but can be reconciled in the simultaneous unsharp measurement and preparation. This reconciliation is expressed as an uncertainty relation however the mutually exclusive feature of complementarity is not discarded. It is possible to recover strict complementarity as a limit case of the appropriate uncertainty relation. One motivation for this study is the effort some authors have made in trying to express the founding features of quantum mechanics in the form of a hierarchy of significance. Here it is shown that complementarity and uncertainty have separate identities but are not completely independent of each other. Consequently, establishing a hierarchy of these features within the present formalism of quantum mechanics is not possible.
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Intracavity optogalvanic spectroscopy for radiocarbon analysis with attomole sensitivityIlkmen, Erhan, January 2009 (has links)
Thesis (Ph. D.)--Rutgers University, 2009. / "Graduate Program in Applied Physics." Includes bibliographical references (p. 88-93).
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Quantitative characterization of nanoscale polycrystalline magnets with electron magnetic circular dichroismSchneider, Claus M., Bürgler, Daniel E., Oppeneer, Peter M., Kocevski, Vancho, Arai, Shigeo, Adam, Roman, Tatsumi, Kazuyoshi, Rusz, Ján, Muto, Shunsuke 01 1900 (has links)
No description available.
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Entropia de Tsallis e sua aplicação em ações da Bolsa de ValoresSouza, Edilson Fernandes [UNESP] 16 September 2009 (has links) (PDF)
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souza_ef_me_rcla.pdf: 327587 bytes, checksum: 4f616c1d7333f2525c13a8a7502cb037 (MD5) / O objetivo do nosso trabalho é a aplicação de um modelo estendido da distribuição do tipo Tsallis e sua aplicação em ações da Bolsa de Valores de São Paulo. Em nosso caso procuramos ações de diferentes setores da nossa economia. Escolhemos então uma ação do setor bancário (Banco do Brasil), do setor de mineração (Vale) e por último uma ação do setor de papel e celulose (Votorantim Celulose e Papel). Na distribuição do tipo Tsallis o índice entrópico q possui um valor constante, em nosso modelo, propomos que ele seja um função exponencialmente decrescente da variável que descreve o tamanho do sistema sendo considerado. Em nosso caso (ações), a variável em consideração é o retorno clássico. Observamos que na maioria dos casos tratados, não houve necessidade do modelo estendido, mas em um caso foi necessário o uso deste para encontrarmos o melhor ajuste para a distribuição de probabilidade. / The objective of our work is the application of an extended version of Tsallistype distribution and its application in the shares of stock exchange of São Paulo. In our case seek shares of different sectors of our economy. Then choose an action of the banking sector (Banco do Brasil), of the mining sector (Vale) and finally an action in the sector of paper and cellulose (Votorantim Celulose e Papel). Tsallis type distribution of the entropy index q has a constant value in our model, we propose that it is an exponentially decreasing function of the variable that describes the size of the system being considered. In our case (stock), the variable account is the classic back. We observed that in most cases, there was no need for the extended model, but in one case it was necessary to use this to find the best fit for the distribution of probability.
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Materiais híbridos de sílica/orgânico dopados com rodamina-B : propriedades luminescentes e emissão laser randômico /Manoel, Diego da Silva. January 2017 (has links)
Orientador: Fábio Simões de Vicente / Banca: Agnaldo Aparecido Freschi / Banca: Tomaz Catunda / Resumo: O processo sol-gel permite a produção de materiais Híbridos Orgânicos/Inorgânicos para aplicações em óptica e fotônica. Materiais Híbridos de Sílica/orgânico unem propriedades da Sílica e dos polímeros orgânicos e permitem a incorporação de diversas moléculas orgânicas na matriz, possibilitando a obtenção de materiais fotoativos avançados. Destas moléculas destacam-se os corantes lasers, como a Rodamina-B, que possui comprimento de onda de emissão bem definido e alta eficiência quântica. Neste trabalho preparamos materiais híbridos de sílica/orgânico via processo sol-gel utilizando como precursores os alcóxidos de silício 3-glicidoxipropiltrimetoxisilano (GPTS) e tetraetilortosilicato (TEOS). Amostras ainda na fase de sol foram dopadas com Rodamina-B em concentrações variando de 0,01 a 5 mmol/L. A fluorescência das amostras foi caracterizada mostrando dependência entre as características da emissão e a concentração de dopante. Os espectros de fluorescência sofrem um deslocamento para a região do vermelho com o aumento da concentração do dopante, enquanto a intensidade de emissão apresenta maior valor para a amostra com concentração de 0,5 mmol/L. Também foram determinados os coeficientes de absorção óptica, que apresentaram comportamento linear com a concentração. A partir das amostras (sol) foram produzidos xerogéis com concentrações de Rodamina-B de 0,0386 a 19,3 mmol/L. Os espectros de fluorescência destes xerogéis também apresentaram deslocamento para a região do vermelho... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Organic-Inorganic Hybrid Materials prepared by sol-gel process have applications in different areas such as optics and photonics. Silica/organic hybrid materials combine the properties from the silica and the organic polymers and can be doped with organic molecules with different optical properties, allowing preparation of advanced photoactive materials. In the wide range of photoactive organic materials one of interest is the Rhodamine-B, a laser dye which presents tunable emission and high quantum yield. In this work we have produced hybrid silica/organic samples derived from 3-glycidoxypropyltrimethoxysilane (GPTS) and tetraethylorthosilicate (TEOS) by sol-gel process. Silica/organic sols were doped with Rhodamine-B concentrations ranging from 0.01 to 5 mmol/L. The fluorescence spectra of the samples were characterized and a relationship between emission characteristics and dopant concentration has been observed. A red shift in the wavelength emission was observed, as the dopant concentration increased and the maximum emission intensity was achieved for the sample with concentration of 0.5mmol/L. Were determined the optical absorption coefficients that showed a linear relation with the concentration. The sol samples were dried and xerogels were obtained and the new concentrations of Rhodamine-B in the solid matrix were determined, ranging from 0.0386 to 19.3 mmol/L. The fluorescence spectra of the xerogels were characterized, showing a red shift as the dopant concentration increased and the maximum emission intensity was achieved for the xerogel with concentration of 6.56 mmol/L. The optical absorption coefficients of these xerogels showed a linear behavior with the dopant concentration. Random laser action for the xerogel with concentration of 19.3 mmol/L was measured using an pulsed laser (532 nm, 8ns), ... (Complete abstract electronic access below) / Mestre
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Development of Magneto-Optic Sensors with Gallium in Bismuth Doped Rare-Earth Iron-Garnet Thick FilmsShinn, Mannix A. 16 February 2018 (has links)
<p> We have investigated the Faraday effect of bismuth-doped rare-earth iron-garnets with varying doping levels of gallium from z = 1.0 to 1.35. We used lutetium to control the film's in-plane magnetic properties and found that gallium doping levels above the compensation point caused a loss of anisotropy control, a canted out-of-plane magnetization in the film, and an extremely weak but linear coercivity above 10 micro-Tesla fields. Using these results we focused on in-plane films to create 8 layer stacks of 500 um thick films to achieve a minimum detectable field of 50 pT at 1 kHz. Unlike previous Magneto-Optic (MO) studies that typically used thin films of approximately 1um thickness, we used approximately 400um thick films to allow experimentation with the final, robust, ideal form the MO sensor would take. We measured what most other MO studies with garnets neglected: the magnetic anisotropy axis or structure within the film. Knowledge of this structure is essential in improving the sensitivity of a stacked MO probe. Studying thick films proved to be key to understanding the magnetic anisotropy and domain properties that can degrade or enhance the sensitivity of the Faraday rotation in bismuth doped rare-earth iron-garnets to an applied magnetic field and to pointing the direction of future research to develop the conditions for rugged magnetometer sensors. </p><p>
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INJECTION CURRENT MODULATED PARITY-TIME SYMMETRY IN COUPLED SEMICONDUCTOR LASERSLuke J Thomas (11028213) 06 August 2021 (has links)
This research investigates the characteristics of Parity Time symmetry breaking in two optically coupled, time delayed semiconductor lasers. A theoretical model is used to describe the controllable parameters in the experiment and intensity output of the coupled lasers. The PT parameters we control are the spatial separation between the two lasers, the frequency detuning, and the coupling strength. We find that the experimental data agrees with the predictions from the theoretical model confirming the intensity behaviors of the lasers, and the monotonic change in PT-threshold as a function of coupling scaled by the time delay. <br>
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Cold amplification and fiber coupling of a super-conducting nanowire single-photon detector / Kall förstärkning och fiberkoppling av en superledande nanotråds enfoton-detektorCohen, Stéphane January 2022 (has links)
Single-photon detectors are an essential tool for quantum photonics: one can harness the quantum properties of single photons for quantum communication as well as use the detectors in low illumination applications.Superconducting nanowire single-photon detectors offer high detection efficiency over a widerange of wavelengths, low dark counts, and a good timing resolution compared to single-photonavalanche diodes.The goal of this master thesis is to fabricate SNSPDs and to design a mount for an opticalfiber onto the SNSPD that can be fabricated inside the nanofabrication facility of KTH. Anamplification stage was designed to be placed inside the cryostat to lower the time uncertaintyof the detection peaks. We designed the fiber mount and the SNSPD using only lithographic processes. We designed a low-noise amplification and biasing system inside the cryostat to lower the amplifier noise compared to amplification at room temperature. / Enstaka fotondetektorer är ett viktigt verktyg för kvantfotonik: man kan utnyttja kvantegenskaperna hos enstaka fotoner för kvantkommunikation samt använda detektorerna i låg belysning.Supraledande nanotrådsdetektorer för enstaka fotoner erbjuder hög detektionseffektivitet överett brett spektralområde, låga sannolikhet för falska detektioner och en god tidsupplösningjämfört med enfotoniga lavindioder. Målet med detta examensarbete är att tillverka SNSPD:er(Superconducting Nanowire Photon Detector) och att utforma ett fäste för en optisk fiber påSNSPD:n som kan tillverkas i KTH:s nanofabrikationsanläggning. Ett förstärkningssteg utformades för att placeras inuti kryostaten för att minska tidsosäkerheten av detektionstopparna.Vi utformade fiberfästet och SNSPD:n med hjälp av enbart litografiska processer. Vi konstruerade ett förstärkningssystem och applicerade en spänning över SNSPD:n med lågt brus inne i kryostaten för att sänka förstärkarbruset jämfört med förstärkning vid rumstemperatur.
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Estudo da influência de parâmetros de manufatura e de caracterização nas propriedades fotocondutivas de filmes de óxidos metálicos processados por solução /Moisés, Lucas Augusto. January 2018 (has links)
Orientador: Lucas Fugikawa Santos / Banca: Gregório Couto Faria / Banca: Cleber Alexandre de Amorim / Resumo: No presente trabalho produziram-se filmes finos transparentes de ZnO depositados pela técnica de spray-pirólise com objetivo de estudar o comportamento de suas propriedades elétricas durante a incidência de luz UV e após a incidência de luz (no escuro). Para tal, foram propostos três designs experimentais do tipo fatorial de dois níveis, um do tipo fatorial fracionário com base no modelo de Plackett-Burman e dois fatoriais completos. Na realização desses experimentos, variou-se parâmetros de produção do filme e também parâmetros experimentais no momento da realização da medida, sendo nove parâmetros no total. Através dos dados obtidos nesses experimentos, obteve-se respostas experimentais. Em cima disso foram realizadas analises estatísticas. Assim, através dessas análises se conheceu quais os fatores experimentais tiveram maior influência em cada uma dessas respostas e os resultados obtidos tiveram um bom acordo com a teoria, indicando a eficácia dos experimentos fatoriais de dois níveis realizados. Por fim, foi realizado medidas de predição e comparado as respostas obtidas nessas medidas com os dados estatísticos obtidos. Através dessa comparação, foi encontrado uma resposta reprodutível, indicando assim a possibilidade aplicação de filmes de ZnO na área de sensores / Abstract: In the present work, transparent thin films of ZnO deposited by the spray - pyrolysis technique were used to study the behavior of their electrical properties during the incidence of UV light and after the incidence of light (in the dark). For that, three experimental designs of the two - level factorial type were proposed, one of the fractional factorial type based on the Plackett - Burman model and two complete factorials. In the performance of these experiments, parameters of production of the film were varied as well as experimental parameters at the moment of the measurement, being nine parameters in total. Through the data obtained in these experiments, experimental responses were obtained. Statistical analyzes were performed on top of this. Thus, through these analyzes it was known which experimental facto rs had the greatest influence on each one of these responses and the results obtained had a good agreement with the theory, indicating the effectiveness of the two - level factorial experiments performed. Finally, prediction measures were performed and the r esponses obtained in these measurements were compared with the statistical data obtained. Through this comparison, a reproducible response was found, thus indicating the possibility of applying ZnO films in the area of sensors / Mestre
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Estudo de processos de degradação de pigmentos de coloração azul e amarela / Study of degradation processes of blue and yellow pigmentsAguero, Natasha Fioretto 23 May 2017 (has links)
Em arqueometria e nas ciências aplicadas, metodologias físicas e químicas são de grande utilidade para estudar diferentes materiais e objetos do patrimônio cultural como pinturas de cavalete, murais, cerâmicas, metais, etc. No caso particular de pinturas, tais análises podem auxiliar na compreensão do processo criativo, dos materiais utilizados pelo artista e do estado de conservação desta obra. No contexto deste último item, podem ser caracterizados sinais de degradação, como a alteração de cores. Dentro do objetivo de compreender a degradação de alguns pigmentos por exposição luminosa, estudaram-se os pigmentos amarelo de cádmio (CdS), amarelo de cromo (PbCrO4), azul de cobalto (CoAl2O4) e cerúleo (Co2SnO4), sendo estes dois últimos também misturados ao branco de zinco (ZnO). Tais estudos foram realizados através de três ensaios com amostras padrões preparadas com estes pigmentos: fotodegradação induzida na linha TGM (Toroidal Grating Monochromator) do Laboratório Nacional de Luz Síncrotron; exposição à luz ultravioleta no simulador solar SOL-UV; e exposição às radiações ultravioleta, visível e infravermelha em uma câmara projetada neste mestrado. Os resultados apontaram para indicativos de alteração em todas as amostras, em especial mudanças no espectro de reflectância na região do visível. Por fim, analisaram-se amostras de tintas obtidas de obras do pintor Candido Portinari que possuíam indícios de alteração cromática. A partir destes fragmentos, construíram-se modelos estratigráficos dos materiais utilizados pelo artista nestas pinturas. / In archeometry and applied sciences, physical and chemical methodologies are very useful for studying different materials and objects of cultural heritage such as easel paintings, murals, ceramics, metals, etc. In the particular case of paintings, such analyses can help in understanding the creative process, the materials used by the artist and the conservation status of this work. In the context of this latter item, signs of degradation, such as color change, can be characterized. In order to understand the degradation of some pigments by light exposure, the cadmium yellow (CdS), chrome yellow (PbCrO4), cobalt blue (CoAl2O4) and cerulean blue (Co2SnO4) pigments were studied, the latter two being also mixed with zinc white pigment (ZnO). Such studies were carried out through three experiments prepared with these pigments: photodegradation induced in the TGM (Toroidal Grating Monochromator) line of the National Laboratory of Synchrotron Light; exposure to ultraviolet light in the SOL-UV solar simulator; and exposure to ultraviolet, visible and infrared radiation in a chamber designed in this master\'s degree. The results pointed out changes in all samples, especially in their reflectance spectrum in the visible region. Finally, samples obtained from works by the painter Candido Portinari that had signs of chromatic alteration were analyzed. Based on these fragments, stratigraphic models of the materials used by the artist in these paintings could be constructed.
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