Teses e dissertações: Recent submissions
Now showing items 41-60 of 337
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Algoritmos quânticos para resolução de equações diferenciais: análise de complexidade e aplicabilidade
(Universidade Federal de São Carlos, UFSCar, Programa de Pós-Graduação em Física - PPGF, Câmpus São Carlos, 11/02/2022)This work consists in a complexity analysis of an algorithm for solving differential equations, which shares common characteristics with other algorithms designed for the same task. Operations such as state preparation, ... -
Propriedades ópticas de filmes semicondutores GaAsBi e GaSbBi
(Universidade Federal de São Carlos, UFSCar, Programa de Pós-Graduação em Física - PPGF, Câmpus São Carlos, 02/05/2022)Bismuth-diluted III-V are interesting materials for possible applications in optoeletronic and spintronic devices. If we add a small amount of Bi in III-V materials, we observe a strong reduction in the band gap energy. ... -
Dos conceitos fundamentais da termodinâmica ao resetting de computadores quânticos
(Universidade Federal de São Carlos, UFSCar, Programa de Pós-Graduação em Física - PPGF, Câmpus São Carlos, 18/04/2022)Thermodynamic has been known and studied for centuries, whereas the field of computing, more specifically quantum computing, is new and currently a lot of research has being done to understand and develop this field of ... -
Sensores baseados em nanofios semicondutores de SnO2: fotodetector de luz UV e sensor de gás
(Universidade Federal de São Carlos, UFSCar, Programa de Pós-Graduação em Física - PPGF, Câmpus São Carlos, 11/04/2022)In this work, sensors employing SnO2 semiconductor nanowires as active layer for gas and light detection were built. SnO2 nanowire samples were grown by VLS (VapourLiquid-Solid) method and morphological and structural ... -
Propriedades óticas e elétricas de dicalcogenetos de metais de transição sobre talco
(Universidade Federal de São Carlos, UFSCar, Programa de Pós-Graduação em Física - PPGF, Câmpus São Carlos, 24/02/2022)Two-dimensional (2D) systems have attracted great attention in the last years, for fundamental physics and in potential applications as optoelectronic devices. There is a great interest in transition metal dichalcogenides ... -
Optimization and application of the quantum adiabatic theorem, and the quantum origin of classical interference
(Universidade Federal de São Carlos, UFSCar, Programa de Pós-Graduação em Física - PPGF, Câmpus São Carlos, 29/03/2022)In this master’s thesis, we developed three different topics. In the first topic, we studied the quantum adiabatic brachistochrone method (QAB) for optimizing adiabatic dynamics. In the first part of this study, we reported ... -
Método de dinâmicas efetivas aplicado na análise da interação qubit-qubit em dispositivos supercondutores: a interação qubit-qubit no contexto da computação quântica
(Universidade Federal de São Carlos, UFSCar, Programa de Pós-Graduação em Física - PPGF, Câmpus São Carlos, 23/02/2022)In this dissertation, we approach some aspects of quantum computing. At first, we detail the Deutsch-Jozsa algorithm and show how to implement it in real IBM quantum computers, available free of charge via remote access ... -
Carrier dynamics of low-dimensional semiconductors: from quantum wells and quantum dots to resonant tunneling devices
(Universidade Federal de São Carlos, UFSCar, Programa de Pós-Graduação em Física - PPGF, Câmpus São Carlos, 22/07/2021)This thesis aims to study heterostructures and devices that play a fundamental role in modern nanoelectronic technologies, focusing on group III-V semiconductor materials, especially arsenide-based systems, for photodetection ... -
Charge carrier dynamics and optoelectronic properties in quantum tunneling heterostructures
(Universidade Federal de São Carlos, UFSCar, Programa de Pós-Graduação em Física - PPGF, Câmpus São Carlos, 17/09/2021)Semiconductor quantum tunneling heterostructures offer a wide range of applications as photosensors, lasers, and circuit elements. However, fundamental questions related to energy transfer mechanisms and the correlation ... -
Raman spectroscopy as a reliable tool for strain analysis in iii-nitride superlattices
(Universidade Federal de São Carlos, UFSCar, Programa de Pós-Graduação em Física - PPGF, Câmpus São Carlos, 02/09/2021)Since its discovery, the Raman effect has been a great ally in the structural investigation of a wide variety of materials, from macro to nanoscale. However, despite the remarkable sensitivity of techniques based on Raman ... -
Estudo do modelo de Hubbard bidimensional não homogêneo via teoria do funcional da densidade
(Universidade Federal de São Carlos, UFSCar, Programa de Pós-Graduação em Física - PPGF, Câmpus São Carlos, 14/07/2021)We implemented the DFT calculation through the Kohn-Sham formalism adapted by the methodology μ-BALDA for the inhomogeneous two-dimensional Hubbard model, which is also implemented experimentally on an ultra-cold atom traps ... -
Engenharia de reservatórios com temperaturas efetivas arbitrárias e máquinas térmicas quânticas para sistemas de spins nucleares
(Universidade Federal de São Carlos, UFSCar, Programa de Pós-Graduação em Física - PPGF, Câmpus São Carlos, 24/05/2021)In this work we show how to engineer reservoirs with different effective temperatures for a single qubit (quantum bit) system. To that end, we built an appropriate interaction between a qubit, that is, a 13C nuclear spin, ... -
Deposição e caracterização de filmes finos do sistema Zn(1-x)CoxO obtidos por spray pirólise para aplicação em sensor de ozônio
(Universidade Federal de São Carlos, UFSCar, Programa de Pós-Graduação em Física - PPGF, Câmpus São Carlos, 19/04/2021)The current concern about reducing the harmful effects of air pollution on environment and human health requires adequate gas sensors that allow an efficient control and monitoring on a wide range of pollutants. This ... -
A study of SnO2 nanowire FET devices: ambipolarity effect induced by UV Light exposure and their use as UV sensors
(Universidade Federal de São Carlos, UFSCar, Programa de Pós-Graduação em Física - PPGF, Câmpus São Carlos, 18/03/2021)In this work, SnO2 nanowires (NW) were grown by the Vapor-Liquid-Solid (VLS) method and used to build single NW FET devices. As-grown samples went through structural and morphological analysis and seven single NW devices ... -
Controle da emissão visível de nanopartículas baseadas em óxido de zinco
(Universidade Federal de São Carlos, UFSCar, Programa de Pós-Graduação em Física - PPGF, Câmpus São Carlos, 25/02/2021)We present a study of the synthesis processes and of the structural, vibrational and optical properties of Zn1-xCdxO nanostructured system. The Zn1-xCdxO samples were synthesized using mechanosynthesis method, in the ... -
Development of seminconductor nanowire materials for electronic and photonics applications
(Universidade Federal de São Carlos, UFSCar, Programa de Pós-Graduação em Física - PPGF, Câmpus São Carlos, 05/12/2019)The thesis is concerned with study of GaAs nanowires fabricated on Si substrate. The possibility of growing III-V semiconductor materials directly on silicon in the form of nanowires is an attractive route to the integration ... -
Filmes finos supercondutores sob um campo magnético inomogêneo: diminuição da profundidade da frente de fluxo magnético
(Universidade Federal de São Carlos, UFSCar, Programa de Pós-Graduação em Física - PPGF, Câmpus São Carlos, 25/03/2021)The phenomenon of superconductivity was discovered by scientist Heike Kamerlingh Onnes in 1911, while studying the resistivity of mercury when cooled below 4,2 K. As predicted by Alexei Abrikosov in 1957, materials from a ... -
Análise de segurança de criptografia quântica baseada em teletransporte
(Universidade Federal de São Carlos, UFSCar, Programa de Pós-Graduação em Física - PPGF, Câmpus São Carlos, 04/02/2021)We prove that the teleportation based quantum cryptography protocol presented in [Opt. Commun. 283, 184 (2010)], which is built using only orthogonal states encoding the classical bits that are teleported from Alice to ... -
Coerência espectral da luz espalhada por átomos frios saturados
(Universidade Federal de São Carlos, UFSCar, Programa de Pós-Graduação em Física - PPGF, Câmpus São Carlos, 27/02/2020)The spectrum of radiation resonantly scattered by a strongly-driven two-level system consists of three peaks called the Mollow’s triplet. In the case of cold atoms, we can approximate their energy level structure by a ... -
Propriedades magnéticas em filmes finos de MoS2 produzidos pelo método de esfoliação em solvente
(Universidade Federal de São Carlos, UFSCar, Programa de Pós-Graduação em Física - PPGF, Câmpus São Carlos, 28/09/2020)In this work, thin films of molybdenum disulfide 2D (MoS2) were prepared at different temperatures (15, 25, 30 and 45 ° C) using the solvent exfoliation method. This process produces changes in the morphology and structure ...