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Estudo por espectroscopia Raman de efeitos de localização das excitações elementares em superredes e em ligas dopadas.
(Universidade Federal de São Carlos, 2005-03-22)
In the present work, the localization properties of the single-particle and collective excitations subjected to a random potential in the AlGaAsSi alloys and in the intentionally disordered GaAs/AlGaAs:Si superlattices (SL ...
Modelo do potencial ótico complexo para estudo de espalhamento de elétrons por moléculas e radicais livres
(Universidade Federal de São Carlos, 2008-04-11)
In this work, we seek a better understanding of the role of the absorption potential involved in the dynamics of electron-atom (-molecule) interactions, in arder to develop a po¬tential model that better represents the ...
Ruídos e processos quânticos fundamentais em íons aprisionados e ondas propagantes
(Universidade Federal de São Carlos, 2002-07-22)
In this work we present a proposal protocol for engineering arbitrary motional states of trapped ions.Our scheme is based on both techniques of quantum state sculpture and projection synthesis. Next, we investigate the ...
Processos Paramétricos em eletrodinâmica quântica de cavidades.
(Universidade Federal de São Carlos, 2004-03-02)
In this thesis we study the interaction between an atom and a cavity mode submitted
to linear and parametric amplifications. The evolution operator of the system was derived
through the technique of time-dependent ...
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 ...
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 ...
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 ...
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 ...
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. ...
Filmes de diamante não-dopados e dopados: um estudo sistemático usando espectroscopia Raman
(Universidade Federal de São Carlos, 2004-11-17)
Diamond films grown by both hot filament (HFCVD) and microwave-plasma (MW-CVD) assisted chemical vapor deposition were investigated. Raman spectroscopy, scan-
ning electron microscopy and X-ray di¤raction were employed ...