Parabolic Quantum Wells
Mostrando 1-11 de 11 artigos, teses e dissertações.
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1. Estudo de poços parabólicos largos de AIGaAs em campos magnéticos altos / Study of wide parabolic quantum wells of AlGaAs in high magnetic fiels
We present the results of experiments and calculations done on AlGaAs Parabolic Quantum Wells (PQWs) grown on GaAs by molecular beam epitaxial tecniques. Transport measurements in n-type and p-type samples with widths between 1000 ºA and 4000 ºA at low temperatures indicate an abrupt increase of the Hall coeficient at a critical field B ¼ 3 T. Our study f
Publicado em: 2007
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2. Electron g-factor and cyclotron effective mass in semiconductor quantum wells under growth-direction applied magnetic fields
The Ogg-McCombe effective Hamiltonian for the electron in the conduction band together with the non-parabolic and effective-mass approximations were used in a theoretical study of the cyclotron effective mass and electron effective Landé g||-factor in semiconductor GaAs-Ga1-xAl xAs quantum wells under an applied magnetic field parallel to the growth directi
Brazilian Journal of Physics. Publicado em: 2006-09
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3. Effects of in-plane magnetic fields on the electronic cyclotron effective mass and Landé factor in GaAs-(Ga,Al)As quantum wells
The dependence of the electron Landé g-factor on carrier confinement in quantum wells recently gained both experimental and theoretical interest. The g factor of electrons in GaAs-(Ga,Al)As quantum wells is of special interest, as it changes its sign at a certain value of the well width. In the present work, the effects of an in-plane magnetic field on the
Brazilian Journal of Physics. Publicado em: 2006-09
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4. Correlated electron-hole transitions in bulk GaAs and GaAs-(Ga,Al)As quantum wells: effects of applied electric and in-plane magnetic fields
The effects of crossed electric and magnetic fields on the electronic and exciton properties in semiconductor heterostructures have been investigated within the effective-mass and parabolic band approximations for both bulk GaAs and GaAs-Ga1-xAl xAs quantum wells. The combined effects on the heterostructure properties of the applied crossed electric/magnetic
Brazilian Journal of Physics. Publicado em: 2006-09
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5. Magnetotransport in Al xGa x-1As quantum wells with different potential shapes
We compare the transport properties for triangular, parabolic and cubic quantum wells. We calculate the transport mobility for electrons belonging to the different subbands. We obtain the energy spacing between first and second subbands from the electron sheet density and compare results for different potential profiles. We find that experimental results are
Brazilian Journal of Physics. Publicado em: 2006-06
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6. "Spin and magnetic properties of the III-V group semiconductors" / "Propriedades magnéticas e de spin em semicondutores do grupo III-V"
We present the results of our investigations concerning MBE grown AlGaAs/GaAs parabolic quantum well (PQW) samples. We focused on the variation of the Landé g factor along the structure of the PQWs, which occur as a consquence of its dependence on the Al content on the alloy AlGaAs. The implications are studied by Hall and Shubnikov-de Haas measurements. Sh
Publicado em: 2006
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7. Molecular beam epitaxy of p-type doped layers for the construction of optoelectronic devices / Epitaxia por feixe molecular de camadas dopadas do tipo p para a construção de dispositivos optoeletrônicos
Durante as últimas três décadas, a epitaxia por feixe molecular se estabeleceu como uma técnica excelente para o crescimento de camadas semicondutoras de alta qualidade, tanto para a construção de dispositivos quanto para a pesquisa básica. No entanto ainda não existe um método universalmente aceito para obter-se camadas dopadas do tipo p nesta téc
Publicado em: 2004
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8. Transporte quântico em poços parabólicos largos / Transportation wide parabolic quantum wells
The gradual progress, or evolution, of the two-dimensional (2D) toward three-dimensional (3D) Landau states was studied in wide parabolic quantum Wells (W = 1000 6000 Å). As transport technique, we used measurements of the magnetoresistence in intense (B = 0 15 T) and tilted ( = 0 90°; perpendicular parallel) magnetic Field at low temperature (T = 50 Mk).
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 25/07/2003
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9. Estudo da dinâmica de caos no gás tridimensional de elétrons de alta mobilidade / Study of the dynamics of chaos in three-dimensional gas in electron of high mobility
A dinêmica caótica, em arranjos de bilhares eletrônicos bidimensionais e tridimensionais , em heteroestruturas semicondutoras de AlxGa1-xAs/GaAs foi estudada tanto de forma experimental como através de simulações numéricas. Como primeira parte, a dinâmica eletrônica caótica em super-redes de antipontos bidimensionais foi tratada sob a influência d
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 12/09/2002
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10. Zeeman effect in Cd1-xMn xTe parabolic and half-parabolic quantum wells
We have investigated the electronic structure of Cd1_xMn xTe parabolic quantum wells and half-parabolic quantum wells heterostructures in the envelope function approximation using the k · p method. We have considered an external magnetic field applied in two different configurations: in the plane of the layer and in the growth direction. The confined states
Brazilian Journal of Physics. Publicado em: 2002-06
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11. Low-temperature electron mobility in parabolic quantum wells
We present a theoretical study on the electron mobility and scattering mechanism in a remotely doped AlGaAs wide parabolic quantum well. Electron mobilities in different subbands are calculated from the self-consistent results of the subband energy and wavefunction in the system. The scattering due to ionized impurities and alloy disorder is considered. We s
Brazilian Journal of Physics. Publicado em: 2002-06