Spintronics
Mostrando 13-21 de 21 artigos, teses e dissertações.
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13. Propriedades eletrônicas de heteroestruturas semicondutoras magnéticas diluídas. / Electronic properties of diluted magnetic semiconductor heterostructures
Neste trabalho e apresentado um estudo, via teoria de massa efetiva multibanda autoconsistente de heteroestruturas de semicondutores magnéticos diluídos, generalizada para incluir parâmetros de diferentes materiais. A interacao magnética e descrita por um modelo de campo médio baseado no mecanismo de troca indireta, com a possibilidade de inclusão de d
Publicado em: 2007
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14. Transport properties of a Ga1-xMn xAs/Ga1-yAl yAs double-barrier
We study the transport properties of a spin filter consisting of a double-barrier resonant tunneling device in which the well is made of a semimagnetic material. Even if the device could be made of several materials, we discuss here the case of a Ga1-xMn xAs/Ga1-yAl yAs system because it can be integrated into the well known AlAs/GaAs technology. We solve th
Brazilian Journal of Physics. Publicado em: 2006-09
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15. A selfconsistent calculation of the transport properties of a double barrier spin filter
A double barrier resonant tunneling device in which the well is made of a semi-magnetic material can work as an efficient spin filter. Today it is possible to make semiconductors that are ferromagnetic at room temperature. Therefore the device studied here has a great potential to be used as a polarizer, an analyzer and other spintronic applications. We disc
Brazilian Journal of Physics. Publicado em: 2006-06
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16. Estudo dos compostos semicondutores de metais de transição - Grupo V para aplicação em spintrônica / AB Initio study of transition metals nitrides for spintronics applications
Recentemente um enorme esforço esta sendo feito na busca de bons materiais para aplicação na nova área emergente da eletrônica, a spintrônica. O estudo teórico tem se mostrado de fundamental importância em tal busca. Na presente dissertação estão alguns dos resultados de um estudo computacional envolvendo cálculos de primeiros princípios em Fís
Publicado em: 2006
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17. Filtros de spin não-magneticos controlados por voltagem / Voltage controlled non-magnetic spin filters
The aim of this work was to study the transport properties of nonmagnetic semiconductor heterostructures: double barrier diodes ? DBD. Our attention was focused on the carrier spin polarization through the structure. First we present the phenomenology behind the carrier transport and how the DBD can act as a spin filter. In the sequence, we present the exper
Publicado em: 2006
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18. "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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19. SPIN AND CORRELATION EFFECTS IN NANOSCOPIC TRANSPORT / EFEITOS DE SPIN E CORRELAÇÃO EM TRANSPORTE NANOSCÓPICO
We investigated spin polarized transport properties through a quantum dot connected with two terminals. An electric current that circulates in our system can have its polarization modulated with an external potential that controls the spin orbit coupling (Rashba effect). We studied the effect of spin polarization n a transistor constituted by a quantum dot w
Publicado em: 2005
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20. First-principles materials study for spintronics: MnAs and MnN
We report ab-initio all electrons density- functional calculations for the electronic structure of the compounds MnAs and MnN, in the zinc-blende phase. They are potential materials for use in fabrication of new functional semiconductors taking advantage of the spin degree of freedom. The aim is the establishing of the semiconductor spin electronics (spintro
Brazilian Journal of Physics. Publicado em: 2004-06
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21. Estudo de propriedades estruturais e magneticas de filmes epitaxiais de MnAs sobre GaAs (001) / Study of the structural and magnetic properties of epitaxial MnAs films on GaAs(001)
Neste trabalho foram estudados filmes finos de MoAs crescidos por epitaxia de feixe molecular em substratos de GaAs (001). As propriedades magnéticas destas hetero-estruturas (filme magnético sobre um substrato semicondutor) são fortemente dependentes das propriedades estruturais do filme de MoAs que foram estudadas detalhadamente utilizando técnicas de
Publicado em: 2004