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Estudo sistemático das propriedades estruturais e magnéticas de amostras policristalinas do sistema PrxY1-xBa2Cu3O7-d
(Universidade Federal de São Carlos, 2008-08-10)
One of the most studied high TC superconductor is the YBa2Cu3O7 (Y-123) as well as the different substitutions on the Y site for different rare earth elements. Generally, this does not show important effects on the magnetic ...
Propriedades de transporte de spins polarizados em heteroestruturas semicondutoras
(Universidade Federal de São Carlos, 2009-06-25)
In this work we used the technique of scattering matrix to calculate the transmissivity of polarized spins in a semiconductor symmetrical double-barrier heterostruture. The dynamics of carriers is described by effective ...
Colisões atômicas controladas em eletrodinâmica quântica de cavidades : emaranhamento como medida da classicalidade do campo de radiação
(Universidade Federal de São Carlos, 2009-08-12)
In this dissertation we presente a study on the entanglement between two identical and noninteracting
two-level atoms, generated by their interaction with only a singl cavity filed mode.
We also show how to calculate the ...
Caracterização ótica de poços quânticos de GaMnAs
(Universidade Federal de São Carlos, 2007-09-12)
In this work, we have studied GaAs/AlAs/Ga1-xMnxAs quantum wells (QWs) with low Mn concentration ( 0 < x < 0,2%). The samples were grown by Molecular Beam Epitaxy (MBE) in high temperature (450 C). The growth conditions ...
"Probabilidades negativas" e tomografia de Qubits
(Universidade Federal de São Carlos, 2007-03-28)
In this dissertation we approached the tomography of discrete systems, understood as the representation
and the reconstruction of states. For the tomography we used distribution functions
of symmetrical pseudo-probabilities. ...
Obtenção, propriedades e fenomenologia de materiais ferroelétricos com estrutura tungstênio bronze
(Universidade Federal de São Carlos, 2007-02-23)
The processing of lead metaniobate (PN) ferroelectric ceramics was optimized, therefore, in
this work, the main details to obtain PN ceramics with density higher than 96 % of the ideal density
are presented and ...
Propriedades de transporte eletrônico em filmes de diamante crescidos por deposição de vapores químicos
(Universidade Federal de São Carlos, 2007-02-27)
In this work it was investigated some fundamental properties of undoped and Borondoped
(p-type) synthetic diamond films. It was investigated the influence of the cleaning
process on the surface s quality in order to ...
Estudo por espalhamento Raman de efeitos anarmônicos e transição de fase do PbTiO3 : Sm3+ induzidos por pressão hidrostática e variação de temperatura
(Universidade Federal de São Carlos, 2007-10-05)
In this work it was investigated, by using Raman spectroscopy, the effect of
the substitucional disorder on the vibrational properties of the ferroelectric
ceramics PbTiO3 doped with Samarium, at different temperatures ...
Transdutores ultra-sônicos piezoelétricos com difração limitada : simulação e construção
(Universidade Federal de São Carlos, 2006-08-18)
The importance of ultrasound limited-diffraction Bessel beams in medical
images, tissue characterization, and estimation of Doppler speed (blood flow) as
well as in many other areas of Physics has increased in the two ...
Processamento e caracterização de cerâmicas eletro-ópticas do sistema ferroelétrico (Pb1-xLax)TiO3
(Universidade Federal de São Carlos, 2006-08-04)
The ferroelectric titanate of lead modified with Lanthanum metal system (or PLT) is the most studied of the perovskite structure. It is known that ceramic bodies with specify compositions and adequately chemical preparations ...