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Estudo das transições de fase em cerâmicas ferroelétricas de PZT e PLZT através de espectroscopia mecânica
(Universidade Federal de São Carlos, 2008-10-08)
Lead titanate zirconate (PZT) and lanthanum-modified lead titanate zirconate (PLZT) ferroelectric ceramics have been great scientific and technologic interest, due to the possibility
of your physics properties can be ...
Efeitos de interações elétron-elétron e spin-órbita nas propriedades magneto-eletrônicas de magneto-transporte de sistemas confinados.
(Universidade Federal de São Carlos, 2003-10-10)
Effects of the direct and exchange electron-electron interaction, external magnetic
field, symmetry of the charge carriers confining potential, radius, material g-factor, and
also of the spin-orbit interaction in zincblende ...
Dispersão dielétrica em materiais ferroelétricos.
(Universidade Federal de São Carlos, 2004-12-13)
In the last decades, the high frequency dielectric response has been one of
the most studied issues in the ferroelectricity area. The main dielectric
characteristic is the strong dependence of the dielectric parameters ...
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 ...
Regras de ocupação e influência de dopantes trivalentes em matrizes cerâmicas transparentes de PLZT 9/65/35
(Universidade Federal de São Carlos, 2009-10-01)
In this work, were investigated the occupancy of rare-earth ions in lattice site of the ferroelectric system (Pb,La)(Zr,Ti)O3, or PLZT. The influence on the structural, microestructural, dielectric, ferroelectric, optical ...
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 ...
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 ...