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Mostrando ítems 31-39 de 39
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 ...
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 ...
Propriedades magneto-óticas e de magneto-transporte de um diodo de tunelamento ressonante contendo Si δ - doping no poço quântico
(Universidade Federal de São Carlos, 2011-03-11)
In this work, we have studied the transport and optical properties of GaAs = AlGaAs resonant tunneling diodes with Si delta-doping at the center of the quantum well. We have studied magneto-transport and polarized resolved ...
Estudo experimental de efeitos de spin em heteroestruturas semicondutoras
(Universidade Federal de São Carlos, 2015-04-28)
In this thesis, we have investigated optical and spin properties of semiconductor
nanostructures. Photoluminescence and magneto-photoluminescence measurements
were performed in high magnetic field (B ≤ 15T), in GaBiAs ...
Domínios ferroelétricos em cerâmicas e materiais nanoestruturados: investigação por microscopia de piezoresposta
(Universidade Federal de São Carlos, 2011-12-07)
In this work, ferroelectric domain structure was investigated by Piezoresponse Force Microscopy (PFM). To this, an Atomic Force Microscope (AFM) has been modified to use it as PFM at room temperature and at high temperatures. ...
Estudo das propriedades estruturais através de espectroscopia Raman de amostras de grafite de poucas camadas (GPC) obtidas por clivagem mecânica
(Universidade Federal de São Carlos, 2011-08-25)
In this work, We report studies on samples of graphite few layers obtained from micromechanical techniques of cleaving Manual of highly oriented pyrolytic graphite (HOPG). In order to checking the number of layers in each ...
Propriedades óticas e de transporte em heteroestruturas semicondutoras contendo GaMnAs
(Universidade Federal de São Carlos, 2011-10-14)
In this work, we have investigated Ga1-xMnxAs/GaAs/AlAs quantum wells (QWs) with low Mn concentration (x < 0.1%) grown by Molecular Beam Epitaxy at substrate temperatures of 400 and 450°C. We have investigated the time-resolved ...
Estudo de nanopartículas para preparação de compósitos com acoplamento magnetoelétrico
(Universidade Federal de São Carlos, 2009-09-03)
In recent years the necessity of new devices, in the electroelectronic industry, has lead to an increasing interest in materials called magnetoelectric (ME) or multiferroic (MF). Multiferroic is the term used to classify ...
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 ...