Search
Now showing items 11-20 of 26
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 ...
Efeitos eletrônicos, elásticos e estruturais em sistemas semicondutores nanoscópicos
(Universidade Federal de São Carlos, 2012-02-16)
The present work aims the study of electronic, elastic and structural properties of a whole class of nanoscopic semiconductors systems, which include quasi-two-dimensional, one-dimensional and zero-dimensional confined ...
Efeito Aharonov-Bohm em partículas neutras
(Universidade Federal de São Carlos, 2011-03-14)
In classical Physics, the motion of an electrically charged particle is affected only by the presence of a magnetic field if the particle enters a region of space in which the field is present. Meanwhile, in quantum Physics, ...
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 ...
Efeitos de spin em diodos de tunelamento ressonante tipo-p
(Universidade Federal de São Carlos, 2012-03-27)
In this work, we have investigated the spin effects in p-i-p GaAs/AlAs resonant tunneling diodes under magnetic field parallel to the tunnel current. The spin-dependent tunneling of carriers was studied by analyzing the ...
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 ...