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Estudo de efeitos quânticos em redes de junções Josephson SNS e SIS com composição Nb-CuxAlyOz-Nb através da indução de vórtices por conseqüência do tamanho de rede
(Universidade Federal de São Carlos, 2009-10-16)
In this thesis we studied the quantum effects in networks of Josephson junctions under the induction of vortices and as a consequence of the size of the sample itself. For this, it also was carried out all the instrumentation ...
Modelos magnéticos com frustração e diluição
(Universidade Federal de São Carlos, 2006-12-08)
In this work, we investigate the effect of dilution and frustration in the thermodynamic properties and the phase diagrams using the quasi-two-dimensional Heisenberg and Ising models. We use the Zubarev Green´s function ...
Estudos de avalanches de vórtices em filmes supercondutores de Nb e MgB2
(Universidade Federal de São Carlos, 2008-10-28)
If a type-II superconductor is cooled down in a zero applied field and subsequently an external field, larger than the first critical field, is applied, vortices enter through the sample borders until they are captured by ...
Origem dos momentos magnéticos localizados em ligas de cromo com metais de transição por oscilações de Friedel
(Universidade Federal de São Carlos, 2006-08-02)
The fundamental magnetic properties of chromium and its alloys Cr(1¡x)Nb(x) and Cr(1¡x)V(x), were investigated with the aim to achieve a better comprehension about the nature of the spin density waves. Was dened the edge ...
Medições destrutivas e não-destrutivas em campos eletromagnéticos e processos não-estacionários em eletrodinâmica quântica de circuitos
(Universidade Federal de São Carlos, 2009-02-10)
Dinâmica de coerência e decoerência de estados em redes de osciladores quânticos dissipativos.
(Universidade Federal de São Carlos, 2004-07-02)
In this thesis we studied the coherence and decoherence dynamics of states in
a network of dissipative quantum oscillators. The coherence dynamics refers to
the swap and recurrence process of states between the oscillators ...
Efeitos da interação de plasma na absorção ótica em super-rede randômica de pontos quânticos.
(Universidade Federal de São Carlos, 2004-09-13)
In this work the ground and first excited states of the electron are calculated
in interacting one-dimensional, two-dimensional lattices and multilayers
of cylindrical quantum dots containing at the most an electron and ...
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 estáticas e dinâmicas de portadores em heteroestruturas semicondutoras.
(Universidade Federal de São Carlos, 2002-10-30)
We have studied the dynamic and the stationary properties of carriers in semiconductor
heterostructures submitted to electric fields AC and DC and to magnetic fields
within the effective-mass approximation based on ...
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 ...