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Processamento e propriedades do sistema ferroelétrico (Li,K,Na)(Nb,Ta)O3 dopado com CuO
(Universidade Federal de São Carlos, 2015-03-09)
The search for new lead-free piezoelectric materials has been a major goal of many scientists in recent years. The main cause is the replacement of widely used lead zirconate titanate (PZT) based ceramics due to the highly ...
Efeito da modulação da topologia do confinamento em sistemas quase zero-dimensionais induzida por campo elétrico
(Universidade Federal de São Carlos, 2015-04-01)
Quantum dots grown by epitaxial techniques for optical and transport studies are usually capped by a layer of the same material on which the QDs were grown. Recently, several studies have shown how the growth parameters ...
Optical and transport properties of p-i-n GaAs/AlAs resonant tunneling diode
(Universidade Federal de São Carlos, 2014-05-26)
In this thesis, we have investigated the optical and transport properties of a p-i-n GaAs-AlAs resonant tunneling diode (RTD). The possibility of controlling and significantly varying the density of carriers accumulated ...
Caracterização magnética de compósitos multiferróicos particulados Pb(Zr0,52Ti0,48)O4/CoFe2O4
(Universidade Federal de São Carlos, 2014-08-26)
This work was studied the magnetic and electrical properties of particulate multiferroic composite Pb (Zr0,52Ti0,48) O4 / CoFe2O4 (PZT / CFO) (0-3 type) prepared by the polymeric method of Pechini and sintered by ultra-rapid ...
Fabricação e caracterização de dispositivos baseados em nanofitas de Óxido de Estanho (SnO2)
(Universidade Federal de São Carlos, 2012-08-06)
The structural and transport features of tin oxide nanobelts synthesized by the vapor-solid method combined with the carbothermal reduction process were investigated in this work. The samples synthesized were characterized ...
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 ...
Dielectric and elastic response of perovskites: modelling and simulation
(Universidade Federal de São Carlos, 2013-09-09)
Nesta tese é estudada a resposta elástica e elétrica das perovskitas. As perovskitas são amplamente utilizadas em aplicações técnicas, sendo fundamental na eletrônica e no campo relativamente novo da nanoeletrônica. Elas ...
Relaxação estrutural em ligas vítreas e parcialmente cristalizadas do sistema Cu-Zr-Al através da técnica de espectroscopia mecânica
(Universidade Federal de São Carlos, 2013-11-08)
In recent years the study of bulk metallic glasses (BMG) is being of great scientific and technological interest due to their unique properties (the lack of long range atomic order in the structure and compositional ...
Mecanismos de condução e relaxação elétrica em cerâmicas multiferróicas de Pb(Fe2/3W1/3)O3 e Pb(Fe1/2Nb1/2)O3
(Universidade Federal de São Carlos, 2013-12-19)
Multiferroic are materials which have at least two of the three ferroics orders: ferromagnetism, ferroelectricity and/or ferroelasticity. The coupling between these properties, make multiferroic materials of great technological ...
Propriedades de transporte em óxidos condutores transparentes (TCOs): In2O3, SnO2 e SnO2:F
(Universidade Federal de São Carlos, 2014-03-14)
In this work we studied some of the structural features and transport in nanostructured metal oxides synthesized by the vapor -solid mechanism (VS) aiming their application in high performance devices. The structural ...