Inserir conteúdos de Física Quântica no Ensino Médio torna-se um desafio para os professores, tanto por uma possível falta de preparo como pela falta de incentivo. Apesar da existência de materiais didáticos disponíveis, raramente os professores sentem-se preparados para abordar tais conteúdos em sala de aula. Além disso, o atual currículo do Ensino Médio bem como o programa ENEM, não estimulam ao ensino do assunto aqui referido. No entanto, em função da importância da abordagem da Física Quântica, e também frente à propagação de versões místicas e de representações sociais, é preciso continuar tentando contribuir para que essa inserção venha a ocorrer futuramente. Nesse sentido, foi elaborada uma unidade de ensino sobre tópicos de Física Quântica com a intenção de estimular o interesse e a curiosidade do aluno. Como referencial teórico foi utilizada a teoria de aprendizagem de David Ausubel, buscando desenvolver uma aprendizagem significativa dos conteúdos selecionados da Física Quântica a partir de conhecimentos prévios existentes na estrutura cognitiva dos alunos. A proposta foi elaborada seguindo os passos das Unidades de Ensino Potencialmente Significativas – UEPS (MOREIRA, 2011) onde, num primeiro momento foi feito o levantamento dos conhecimentos prévios dos alunos, em seguida foi apresentado o conteúdo de uma forma mais geral e, a partir daí, cada assunto foi abordado de forma mais específica, visando à diferenciação progressiva e à reconciliação integradora. Os conceitos abordados foram quantização, incerteza, estado e superposição de estados, apresentados de acordo com os passos da UEPS. A implementação do trabalho foi realizada em quatro turmas de 3ª série do Ensino Médio da E. E. E. M. Carlos Antonio Kluwe, em Bagé, RS, durante os meses de outubro, novembro e dezembro de 2011. As quatro turmas, denominadas A, B, C e D, foram divididas em dois grupos. O primeiro grupo, formado pelas turmas A e B iniciou as atividades em 10 de outubro de 2011 e o segundo grupo, formado pelas turmas C e D iniciou as atividades em 31 de outubro. Dentre as atividades desenvolvidas são analisados de forma qualitativa os mapas mentais e mapas conceituais elaborados em duplas, bem como a comparação entre eles, e são mostrados os trabalhos livres confeccionados pelos alunos e o jornal de cada turma Ainda são apresentados alguns comentários de estudantes sobre seu desenvolvimento na compreensão dos conceitos abordados na proposta. A análise feita a partir dos resultados obtidos forneceu indícios de aprendizagem significativa, que é o objetivo de uma UEPS. São apresentados também alguns comentários que indicam a boa receptividade da proposta, que encoraja novas aplicações. / It has become a challenge to high school teachers to include contents of quantum physics in the school curriculum not only for the lack of due preparation but for the scarcity of incentive. In spite of available educational resources, teachers seldom feel ready to approach such contents in the classroom. Furthermore, the present high school curriculum as well as the National High School Exam (ENEM) do not seem to encourage the teaching of quantum physics. Nevertheless, because of the relevance of quantum physics and the dissemination of its mystical versions with their social representations, it is necessary to continue attempting at contributing to make this insertion possible in the near future. In this sense, a teaching unit on topics of quantum physics was developed with the purpose of motivating the students ’ interest and curiosity. David Ausubel’s theory of meaningful learning was used a its theoretical framework, so as to facilitate the occurrence of meaningful learning of the chosen contents of quantum physics based on the students’ prior knowledge about the subject. The proposal was developed in agreement with the steps of the Potentially Meaningful Teaching Units – PMTU (Moreira, 2011), according to which the first step was to make a survey of the students’ prior knowledge followed by a general presentation of the contents. From there on, each topic received a more specific/extensive treatment aiming at progressive differentiation and integrative reconciliation. The concepts involved in this study were quantization, uncertainty, state, and superposition of states and they were presented according to the PMTU’s steps. Implementation of this proposal occurred in four different classes of the 3rd year of high school at the State School E.M. Carlos Antonio Kluwe, Bagé, RS, Brazil, from October to December of 2011. These four classes, named A, B, C, and D, were divided into two groups. The first one, formed by classes A and B, started their activities on the October 10, 2011, while the second group, classes C and D, started them on October 31, 2011. The activities performed by the students, such as mind maps and concept maps drawn in pairs, as well as their comparison were qualitatively analysed. There are also shown free-choice works the students produced, as well as the newspaper that each of the classes put together. In addition, some of the students’ comments on their own development regarding the concepts approached in this proposal are presented. The analysis based on obtained results suggested evidence of the occurrence of meaningful learning, which is the aim of a PMTU. Furthermore, some comments that might indicate a fair receptivity to the proposal are also set forth since they seem to encourage new implementations of this proposal.

A simulação de cores corresponde à essência do processo de síntese de imagens realistas. Em se tratando de minerais, a presença de uma dada impureza, ou uma variação de sua concentração, pode fazer com que alguns materiais sofram alterações dramáticas em suas cores. Por exemplo, enquanto o quartzo puro é transparente, a ametista é um tipo violeta de quartzo, cuja cor é determinada pela presença de traços de ferro. A quantidade de ferro define o matiz percebido. A cor apresentada por um mineral pode ser determinada com base no seu espectro de absorção. No entanto, a definição de todas as variações possíveis é impraticável e, portanto, tal informação está disponível apenas para um subconjunto dos minerais existentes. Esta dissertação apresenta uma proposta para estimar a cor de ágatas, bem como para simular as cores de ágatas sintéticas (inexistentes). A abordagem utilizada baseia-se nos fundamentos da teoria quântica, e parte de uma descrição da molécula de sílica que se deseja simular. À esta, pode-se adicionar quantidades diferentes de impurezas e alterar o número de átomos incluídos na simulação. O resultado obtido é o espectro de absorção do mineral, que pode então ser utilizado para determinar a cor da ágata com a composição desejada. Embora uma simulação detalhada de todo o processo seja uma tarefa computacionalmente extremamente cara, esta dissertação apresenta alguns resultados que corroboram com a correção da solução proposta. Também é apresentada uma técnica independente que pode ser utilizada para definir um volume de ágata com base em uma imagem 2D. / Color simulation is the essence of realistic image synthesis. In the case of minerals, the presence of a given impurity, or a variation of its concentration, can cause some materials to experience dramatic changes in color. For instance, while pure quartz is transparent, amethyst is a violet type of quartz, whose color is determined by the presence of traces of iron. The amount of iron defines the perceived hue. The color presented by a mineral can be determined based on its absorption spectrum. However, defining all possible variations is impractical and, therefore, such information is available only for a subset of the existing minerals. This thesis presents an approach for simulating the colors of existent agates, as well as for predicting the colors for (non-existent) synthetic ones. The approach is based on the fundamentals of quantum theory, and starts with the description of the silica molecule one wants to simulate. One can add different amounts of impurities, and alter the number of atoms included in the simulation. The obtained result is the absorption spectra of the mineral, which can then be used for determining the color of the agate with the desired composition. Although a detailed simulation of the entire process is extremely computationally-expensive, the thesis presents some results that corroborate the correctness of the proposed solution. It also introduces a standalone technique for defining agate volumes based on 2D images of agates.

Apresenta-se um estudo preliminar a respeito das possíveis representações sociais da Física Quântica entre estudantes de diferentes grupos sociais. Após levantamento prévio sobre associações possíveis para a expressão "Física Quântica", foi elaborado um questionário composto por um teste de associação escrita de conceitos (TAEC) e um teste de associação numérica de conceitos (TANC). Responderam ao questionário 494 pessoas, divididas em três grupos: graduandos no curso de Física, estudantes de outros cursos superiores e alunos de Ensino Médio. As respostas aos questionários foram analisadas utilizando estatística multidimensional, o que permitiu a obtenção de diagramas que refletem a estrutura conceitual compartilhada pelos grupos sociais investigados. À luz dos referenciais teóricos da aprendizagem significativa e das representações sociais, foi possível verificar a existência ou não destas representações, que podem atuar como subsunçores para o ensino de Física, juntamente com outras ideias que compõem a ecologia representacional mental do aprendiz. Algumas dessas ideias podem ter sofrido a influência de meios de divulgação, como mídia, livros e filmes. Esses meios auxiliam na propagação de conceitos científicos - ou quase científicos - influenciam o conhecimento das pessoas, por isso se faz necessário investigar qual o significado atribuído a tais conceitos na elaboração de representações sociais. Os resultados indicam a existência de representações sociais compartilhadas entre sujeitos de alguns grupos investigados, permitindo sua identificação e caracterização. Foram encontrados indícios da influência dos meios de divulgação nas representações sociais dos alunos de Ensino Médio, que devem ser mais bem estudados em trabalhos futuros. / A preliminary study regarding possible social representations of quantum physics among students from different social groups is described. Based on an initial survey on word associations to the expression "quantum physics" a questionnaire was constructed including a test of written concept associations (WCA) and a test of numerical concept association (NCA). This questionnaire was answered by 494 students, divided into three groups: physics undergraduate students, high school students, and undergraduate students from subjects other than physics. Data was analysed using the multidimensional scaling technique which provided spatial diagrams that reflect the conceptual structure shared by the investigated social groups. In the theoretical framework of the meaningful learning and social representations theories it was possible to gather evidences of the existence or not of social representations which may act as subsumers in the learning of physics together with other representations that constitute the mental representational ecology of the learners. Some of these representations might be an effect of information provided by books, movies and other media. This media disseminate information regarding scientific - or almost scientific concepts - and influence people's knowledge. Given that previous knowledge is the main variable influencing the acquisition of knew knowledge it is important to investigate the social representations resulting from this dissemination of information. Research findings suggest the existence of social representations about quantum physics shared by some of the subjects and groups studied. Specially in the case of high school students some evidence was obtained about the existence of social representations that should be more explored in future studies.

Ce travail a pour objet d'évaluer l'apport de la physique quantique à la compréhension du phénomène de la conscience. Les modèles « classiques » de la conscience proposés actuellement laissent en suspens deux questions importantes: (a) l'explication de la synchronisation de régions éloignées du cerveau qui semble nécessaire à la construction de percepts conscients ; (b) la question du fossé explicatif qui existe entre l'expérience subjective, relevant de ce que le sujet est capable de ressentir de façon privée, et la description de ses corrélats neurophysiologiques dans le langage de la science, à la troisième personne. Les approches quantiques de la conscience sont systématiquement exposées et critiquées. Le « modèle dissipatif du cerveau »proposé par Vitiello et Freeman semble corroborer les données expérimentales et pourrait ainsi contribuer à résoudre cette dernière question (a). Ce modèle utilise une propriété fondamentale de la théorie quantique des champs selon laquelle la brisure spontanée de symétrie au sein d'un système physique donne lieu à l'émergence d'une dynamique collective pour ce système. Les modèles, relavant de la conception du monismeneutre, qui ont développés par Bohm et Hiley, et, plus récemment, par Atmanspacher et Primas, utilisent la théorie quantique pour son pouvoir expressif (concepts de complémentarité et d'intrication) et non comme une théorie de la seule matière pour bâtir une représentation unificatrice du phénomène de la conscience. Ils permettent de dissoudre la question (b) du fossé explicatif. Nous proposons enfin de prolonger et d'appliquer,plus généralement, ce mode de représentation au domaine psychosomatique. / This work aims to assess the contribution of quantum physics to the understanding of the phenomenon ofconsciousness. The "classical" models of consciousness cannat deal with two important questions: (a) thesynchronisation of distant parts of the brain which seems necessary to the construction of conscious percepts;(b) the question of the explanatory gap that exists between subjective experience, which is a private feeling, andthe description of its neurophysiological correlates in the language of science, at the third persan. The quantumalternatives of current models of consciousness are systematically exposed. Vitiello's and Freeman's "dissipativemadel of the brain" seem to corroborate experimental data and could thus contribute to solve question (a). Thismadel appeals to a fundamental property of quantum field theory according to which a spontaneous symmetrybreaking in a physical system (as it happens, the breaking of the rotational symmetry of dipolar molecules of thebrain) gives rise to a collective dynamics for this system. The models, relevant to the neutra! monism conception,that have been developed by Bohm and Hiley and, more recently, by Atmanspacher and by Primas use quantumtheory for its expressive power (concepts of complementarity and entanglement) to build a unifyingrepresentation of the phenomenon of consciousness. They lead to the dissolution of the question (b) of theexplanatory gap. ln the end, we suggest to extend this mode of representation and to apply it, more generally, tothe psychosomatic domain.

L'isolement du graphène a suscité un grand intérêt vers la recherche d’applications potentielles de ce matériau unique et d'autres matériaux bidimensionnels (2D) pour l'électronique, l'optoélectronique, la spintronique et de nombreux autres domaines. Par rapport au graphène, les dichalcogenides de métaux de transition (TMD) 2D offrent l'avantage d'être des semi-conducteurs, ce qui permettrait de les utiliser pour des circuits logiques. Au cours des dix dernières années, de nombreux développements ont déjà été réalisés dans ce domaine où les opportunités et les défis coexistent. Cette thèse présente les résultats de simulations de transport quantique d’une nouvelle structure de dispositif logique à très faible consommation à base de matériaux bidimensionnels : le transistor à effet tunnel à base d’hétérostructures verticales de TMDs 2D. A cause de leur petite taille, ces dispositifs sont intrinsèquement dominés par des effets quantiques. Par conséquent, l’adoption d’une théorie générale du transport s’impose. Le choix se porte ici sur la méthode des fonctions de Green hors équilibre (NEGF), une approche largement utilisée pour la simulation du transport électronique dans les nanostructures. Dans la première partie de cette thèse, les matériaux 2D, leur synthèse et leurs applications sont brièvement introduits. Ensuite, le formalisme NEGF est illustré. Cette méthode est ensuite utilisée pour la simulation de deux structures de transistor à effet tunnel vertical basées sur l’hétérojonction van der Waals de Mos2 et WTe2. La description du système se base sur un modèle de masse effective calibré avec des résultats ab-initio (afin de reproduire la structure de bandes dans l’intervalle d’énergie intéressé par les simulations de transport) et aux mesures expérimentales de mobilité (pour le couplage électron-phonon). Les résultats non seulement démontrent la possibilité d’obtenir une forte pente sous seuil avec ce type de transistors, mais présentent une étude de la physique qui en détermine les performances en fonction de leur géométrie et de l’interaction entre électrons et phonons. Dans la dernière partie, les effets du malignement rotationnel entre les deux couches 2D sont investigués. Expérimentalement, ce type de désordre est difficile à éviter et peut considérablement affecter les performances du transistor. Par le moyen de simulations quantiques précises et d’analyses physiques, cette thèse montre les défis à relever dans la conception des transistors à effet tunnel à base de matériaux 2D performants. / The successful isolation of graphene in 2004 has attracted great interest to search for potential applications of this unique material and other newborn members of the two-dimensional (2D) family in electronics, optoelectronics, spintronics and other fields. Compared to graphene, the 2D transition metal dichalcogenides (TMDs) have the advantage of being semiconductors, which would allow their use for logic devices. In the past ten years, significant developments have been made in this area, where opportunities and challenges co-exist.This thesis presents the results of quantum transport simulations of novel 2D-material-based tunnel field-effect transistors for ultra-low-power digital applications. Due to their size, such devices are intrinsically dominated by quantum effects. This requires the adoption of a fairly general theory of transport, such as the nonequilibrium Green's functions (NEGF) formalism, which is a method extensively used for the simulation of electron transport in nanostructures.In the first part of this thesis, a brief introduction about the 2D materials, their synthesis and applications is presented. Then, the NEGF formalism is concisely reviewed. This approach is applied to the simulation of two different models of vertical tunnel field-effect transistors based on 2D-TMD van der Waal heterojunctions (MoS2 and WTe2). To properly describe the system, a coupled effective mass Hamiltonian has been implemented and carefully calibrated to experimental measurements and density functional theory to reproduce the band structure in the energy range of interest for the simulations.This thesis not only demonstrates the ultra-steep subthreshold slope potentially expected for these devices, but also provides a physical insight into the impact of the transistor geometry on its performances. In the last and more exploratory part of the manuscript, the effect of rotational misalignment within the two layers of the heterostructure is investigated. Experimentally, such a disorder is difficult to avoid, and it can substantially affect the device performances.Through accurate quantum simulations and deep physical analysis, this study sheds light on the design challenges to be addressed for the development of efficient tunnel field-effect transistors based on 2D materials.

The objective of this thesis was to investigate whether the addition of carbon nanofibers had an effect on the splitting tensile strength of Hydro-Stone gypsum concrete. The carbon nanofibers used were single-walled carbon nanotubes (SWNT), buckminsterfullerene (C60), and graphene oxide (GO). Evidence of the nanofibers interacting with gypsum crystals in a connective manner was identified in both 1 mm thick concrete discs and concrete columns possessing a height of 2 in and a diameter of 1 in. Before imaging, the columns were subjected to a splitting tensile strength test. The results illustrate that while there is a general decrease in strength with an increase in nanofibers for the nanotubes and graphene oxide, the addition of C60 did not noticeably effect the strength. This trend is consistent with trends determined by previous studies.

Apresentamos, nesta tese, uma investigação sobre a estabilização ontológica do fóton, um actante inicialmente articulado no contexto da primeira revolução da Física Quântica. Partindo dos Estudos da Ciência de Bruno Latour, entendemos a ciência como uma rede que se estende por diferentes setores da sociedade e que, portanto, lida com diferentes gêneros do discurso. Além de identificar a importância do gênero científico (artigos seminais) no processo de autonomização dos fatos científicos, também reconhecemos que, na comunidade da Física, os livros didáticos, ou manuais de instrução, tem papel crucial no estabelecimento dos problemas exemplares bem como das teorias hegemônicas, tanto que, hoje, é possível um físico se formar sem estudar os artigos originais sobre Física Quântica. Ademais, os livros didáticos de ciências da Educação Básica são, atualmente, responsáveis pela extensão da rede científica para além dos laboratórios, autonomizando actantes como o fóton em esferas mais amplas da sociedade, papel que Latour poderia chamar de representação pública. O objetivo desta pesquisa é investigar a interação entres esses três gêneros do discurso (artigos seminais, livros didáticos de ensino superior e livros didáticos de ensino médio) e interpretar como que a estabilização ontológica do fóton é mediada por cada um deles. Ao fazer isso, estamos estendendo o programa de pesquisa de Latour em, pelo menos, três sentidos. Primeiramente, incluímos o papel do contexto didático na rede da ciência. Segundo, nossos objetos de investigação estão separados por um intervalo temporal maior do que o usual (aproximadamente cem anos). E, por fim, enquanto Latour dedica-se, principalmente, ao estudo de ciências empíricas, nosso trabalho volta-se para assim chamada Física Teórica, levantando questões ontológicas não discutidas originalmente por Latour. Para dar conta dessa extensão, o presente trabalho está dividido em duas partes. A parte I (Referencial Teórico) traz três artigos sobre as ideias de Bruno Latour e as possibilidades de sua aplicação na pesquisa em Educação em Ciências, o que temos chamado de Sociologia Simétrica da Educação em Ciências ou Estudos da Educação em Ciência. A parte II (Estudos Empíricos) traz quatro artigos (dois sobre as relações entre artigos seminais e livros de ensino superior e dois sobre as relações entre artigos seminais, livros de ensino superior e livros de ensino médio). O primeiro estudo empírico traz uma análise metalinguística do artigo original de Einstein de 1905 em que o quantum é articulado pela primeira vez sem que se precisasse recorrer a nenhum laboratório. No segundo artigo, apresentamos uma análise conceitual e matemática dos artigos de de Broglie e usamos as ideias de Latour para discutir o papel dos livros didáticos na autonomização de sua teoria. No terceiro artigo, analisamos visões epistemológicas em livros didáticos de Física aprovados no Plano Nacional do Livro Didático do Ensino Médio de 2015. E, no quarto artigo, discutimos a narrativa sobre o fóton nesses livros a partir de uma articulação teórica entre ideias de Latour e Bakhtin. Nossos principais resultados apontam o papel articulador da matemática na estabilização de actantes físicos e o papel ativo dos autores de livros didáticos na estabilização do fóton a partir da hibridização de diferentes visões e do uso de mecanismos de causação reversa. / We present an investigation about the ontological stabilization of photon, an actant articulated initially in the context of the first Quantum Revolution. Departing from Bruno Latour’s Science Studies, we take Science as a network spread through different sectors of society and which deals with different speech genders. Besides of identifying the importance of the scientific gender (scientific papers) in the process of autonomation of scientific facts, we also recognize that, in the Physics community, textbooks play a crucial role in the establishment of traditional problems as well as hegemonic theories. Nowadays, someone can conclude an undergraduate course on Physics without having read any of the original papers about Quantum Physics. Furthermore, textbooks in Basic Education are responsible by the extension of the scientific network beyond laboratories, autotomizing actants like the photon in wider spheres of society, what Latour would call public representation. The goal of this research is to investigate the interaction among these three speech genders (original papers, undergraduate textbooks and high school textbooks) and to interpret how the ontological stabilization of photon is mediated by each of them. By doing so, we are extending Latour’s research program in at least three ways. First, we include the didactic context in the science network. Second, our objects of investigation are separated in time by a greater gap (about a hundred years). And third, while Latour studied chiefly the empirical sciences, our work is directed towards the Theoretical Physics, raising ontological questions that were not discussed by Latour. To allow this extension, the work is divided in two parts. Part I (Theoretical Framework) presents three papers about Bruno Latour’s ideas and the possibilities of their application in the research on Science Education, what we have called The Symmetric Sociology of Science Education. Part II (Empirical Studies) presents four papers (two about the relation between original papers and undergraduate textbooks and two about the relation between original papers and high school textbooks). The first empirical study presents a metalinguistic analysis of 1905 Einstein’s paper in which the quantum is articulated by the first time without requiring any laboratory trial. In the second paper, we present a conceptual and mathematical analysis of de Broglie’s papers and we use Latour’s ideas to discuss the role of textbooks in the atomization of his theory. In the third paper, we analyze the epistemological visions present in the Physics textbooks approved by the 2015 National Plan of Textbook. In the fourth paper, we discuss the narrative about the photon present in these books departing from a theoretical articulation between Latour’s and Bakhtin’s ideas. Our chief results point to the articulating role of mathematics in the stabilization of physical actants and the active role of textbooks authors in the stabilization of photon through the hybridization of different visions and the use of the mechanisms of reverse causation.

La supraconductivité par effet de proximité est un phénomène apparaissant à basse températures qui confère des propriétés supraconductrices à un métal normal cohérent de phase connecté à des électrodes supraconductrices. C'est aussi un outil puissant de la physique mésoscopique, car il est sensible aux différents régimes de transport à basse température. En particulier, nous avons utilisé cet effet afin de révéler les propriétés électroniques spéciales de nanofils de Bi monocrystallins. Dans ce système, le transport est dominé par la surface. De plus, la présence de fort couplage spin-orbite dans le Bi à basse dimension influence profondément sa structure de bande : la bicouche de Bi orienté selon la direction (111) a été prédite d'être isolante dans le volume, mais conductrice sur les bords. Cet effet, appelé l'effet Hall quantique de spin donne lieu a deux états chiraux contra-propageants, qui sont insensibles au désordre tant que la symétrie par renversement du temps est préservée.A travers l'observation de la robustesse du courant critique à fort champ magnétique dans plusieurs échantillons, en même temps que des intérférences de type SQUID à bas champ magnétique, nous avons montré l'existence d'états de bord 1D portant le supercourant. La mesure de la relation courant-phase grâce à la technique de SQUID asymétrique sur un nanofil caractérisé auparavant a été réalisée et démontre que ces canaux sont en fait balistiques. Ces résultats sont compatibles avec des simulations de type liaisons fortes, qui étendent les résultats connus pour la bicouche de Bi (111) aux systèmes de type nanofil. L'ajout d'un champ Zeeman dans le plan permet d'observer des transitions 0-π, révélant ainsi des croisements de niveaux induits par la séparation en spin des états d'Andreev. Enfin, des mesures de la susceptibilité dynamique de ce système via des mesures de spectroscopie micro-onde ont été mises en place, et pourraient démontrer de manière univoque la propriété de protection topologique contre le désordre, d'après nos simulations numériques. / The superconducting proximity effect is a phenomenon occurring at low temperatures that conveys superconducting properties to a phase coherent normal metal sample connected to superconducting electrodes. It is also a powerful tool in mesoscopic physics because it is sensitive to different transport regimes at low temperatures. In particular, we have used this effect to reveal the special electronic transport properties of single crystal Bi nanowires. In this system, the transport is dominated by surface states. Moreover, the presence of strong spin-orbit coupling in Bi at low dimensions deeply influences its electronic structure : it was predicted that (111) oriented Bi bilayer are insulating in the bulk, but conducting along the edges. This so called Quantum Spin Hall Effect (QSHE), gives rise to counterpropagating chiral edge states, that are protected against disorder as long as time reversal symmetry is present.Through the observation of the resilience of the critical current in several samples at high magnetic field, along with SQUID-like interference pattern at low magnetic field, we showed the existence of supercurrent carrying 1D edge states. The measurement of the current-phase relation using the asymetric SQUID technique on a previously characterized nanowire was realized and further demonstrates that these edge states are ballistic. These findings are consistent with tight-binding simulations that extend the known results for (111) Bi bilayer to nanowire-like system. The addition of an in-plane Zeeman field allows one to observe 0-π transitions, thereby revealing spin-splitting induced Andreev level crossings. Finally, microwave spectroscopy measurement of the dynamical susceptibility in this system are initiated, that could reliably demonstrate the property of protection against disorder according to numerical simulations.By exploring Bi at low dimensions, this thesis paves the way towards the exploration of electronic states fully protected from disorder.

abstract: Recent developments inspired by string theoretic considerations provide multiple maps between gravitational and non-gravitational degrees of freedom. In this dis- sertation I discuss aspects of three such dualities, the gauge/gravity duality and how it applies to condensed matter systems, the fluid-gravity duality, and the color-kinematics duality. The first of these, colloquially referred to as holography, in its simplest form posits a mapping of d-dimensional conformal field theory (boundary) partition functions onto d+1 dimensional gravitational(bulk) partition functions, where the space-time carries a negative cosmological constant. In this dissertation I discuss the results of our calculations examining the emergence of Fermi-surface like structures in the bulk spacetime despite the absence of explicit Fermions in the theory.Specifically the 4+1 dimensional Einstein-Maxwell-Chern-Simons theory with scalar degrees of freedom, with and without symmetry breaking is considered. These theories are gravity duals to spatially modulated gauge theories. The results of calculations presented here indicate the existence of a rich phase space, most prominently Fermi shells are seen. The second set of dualities considered are the color-kinematic duality, also known as the double-copy paradigm and the fluid-gravity duality. The color-kinematic duality involves identifying spin-2 amplitudes as squares of spin-1 gauge amplitudes. This double copy picture is utilized to construct “single copy” representations for space- times where Einstein’s equations reduce to incompressible Navier-Stokes equations. In this dissertation I show how spacetimes that characterize irrotational fluids and constant vorticity fluids each map to distinct algebraically special spacetimes. The Maxwell fields obtained via the double-copy picture for such spacetimes further provide interesting parallels, for instance, the vorticity of the fluid is proportional to the magnetic field of the associated gauge field. / Dissertation/Thesis / Doctoral Dissertation Physics 2020

Many are beginning to see the promise that the quantum world has offered those who manage and lead organizations (Wheatley, 1992; Zohar, 1997). The Newtonian world is one in which all "things" are reduced to their smallest parts, separated, divided, and analyzed with predictability, with complete control being the ultimate goal. The quantum world is one of infinite possibilities, infinite fields of influence, and infinite relationships. The hallmark characteristics found in a manager who has been schooled in the quantum sciences are flexibility, responsiveness, synchronicity, serendipity, creativity, innovation, participation, and motivation. In a quantum organization there is the constant awareness of the whole system, but there is also diversity (wave or particle), which allows for self-organization that is based on the environment and its requirements. In the quantum world many paths lead from A to Z, and depending on the path chosen, numerous realities wait to unfold. It was the goal of this research to explore the changing of leader behaviors through exposure to the models and theories found in quantum physics. From a quantum perspective this behavior change is possible; the only question is the readiness, willingness, and ability of the leaders to allow their behaviors to be surfaced and challenged. These are indeed the greatest challenges for all people as they proceed through life and work - readiness for change, willingness to change, and ability to surface key areas where change is needed.