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Correlacões quânticas: medidas e simetrias
(Universidade Federal de São Carlos, 2011-06-17)
In this thesis, we explore two sort of quantum correlations: entanglement and quantum discord. We present a geometric method to identify and measure the degree of entanglement based on symmetries of vectors and matrices ...
Processos estocásticos de reação e difusão na rede e cadeias quânticas
(Universidade Federal de São Carlos, 2000-06-02)
In this work we investigate some reaction-difusion stochastic processes on the lattice. In particular, we determine the universality classes of critical behavior of a nonequilibrium surface growth process and of the basic ...
Propriedades estruturais e magnéticas do isolante topológico Bi2Se3 com aglomerados de FexSey
(Universidade Federal de São Carlos, 2016-03-29)
In this work, we discuss the growth of Fe containing Bi2 Se3epilayers on the
GaAs(111) substrate by molecular beam epitaxy (MBE) with Fe contents of in the 8-
20% range. It is shown that Bi2 Se3 film thin are grown with ...
Teletransporte quântico na presença de ruído
(Universidade Federal de São Carlos, 2016-04-01)
The main focus of this work is to explore the feasibility of conducting the
teleportation protocol in scenarios where the presence of an external environment
reduces the purity of the input state and the transmission ...
Transição de fase quântica e modelos de spins frustrados
(Universidade Federal de São Carlos, 2007-03-15)
In this thesis, we will study the quantum phase transition of frustrated quantum spin
models: (i) van Hemmen model ( S = 1) with transverse and anisotropic biaxial field (ii)
Heisenberg model (S = 1/2 ) with competitive ...
Propriedades magnéticas de BiMn2O5 e Fe3O2BO3
(Universidade Federal de São Carlos, 2018-02-26)
In this work, an exploration of the synthesis and magnetoelectric properties of single-crystals of BiMn2O5 and a systematic study of the magnetic properties of Fe3O2BO3 are presented. Despite the unlike composition, both ...
Técnicas de difração de elétrons e de caracterizações elétricas e térmicas combinadas para análise de transformações de simetria em estruturas perovskitas distorcidas : caso das soluções sólidas (Pb1-xCax)TiO3
(Universidade Federal de São Carlos, 2017-03-03)
The main objective of this work was the unequivocally determination of the crystal symmetry
of distorted perovskite structure by direct and indirect methods, with the solid solution system
Pb1-xCaxTiO3 (PCT) as the case ...
Estudos sobre a inclusão da correlação eletrônica do alvo no espalhamento elástico elétron-molécula e sobre a ionização molecular por impacto de elétrons
(Universidade Federal de São Carlos, 2003-12-10)
In this work we present two contributions to the electron-molecule collision theory. Firstly, we present a new theoretical procedure to introduce the target electronic correlation in the elastic electron-molecule scattering. ...
Emaranhamento intrínseco em sistemas tipo-Dirac
(Universidade Federal de São Carlos, 2018-03-06)
Dirac equation is supported by a $SU(2) \otimes SU(2)$ group structure, such that its solutions describe two discrete degrees of freedom, intrinsic parity and spin, which in general are entangled. In this work we will ...
Estudos de vidros fluoroboratos e fluorogermanatos de chumbo, através de técnicas de espectroscopia óptica e de ressonância magnética
(Universidade Federal de São Carlos, 2018-12-04)
In this work two studies on rare earth−doped (Eu3+, Yb3+) lead fluorogermanate (GeO2−PbO−PbF2) and fluoroborate glasses (B2O3 −PbO −PbF2) were investigated. The main advantages of these glasses are their chemical stability ...