Nanoscopic Systems
Mostrando 1-7 de 7 artigos, teses e dissertações.
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1. Simulações de sensores de gás nanoscópicos baseados em nanotubos de carbono: estrutura eletrônica e transporte de elétrons / Computational simulations of nanoscopic gas sensors based on carbon nanotubes: electronic structure and electronic transport
Since their discovery by S. Iijima in 1991, carbon nanotubes have been considered as one of the most promising nanostructured materials for the development of new nanoscopic electronic devices. Due to its high surface area to volume ratio, this material stands out as a candidate for possible gas sensoring applications. In this thesis, we have studied, by mea
Publicado em: 2011
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2. EFEITOS DE MUITOS CORPOS NAS PROPRIEDADES DE TRANSPORTE EM SISTEMAS NANOSCÓPICOS. EFEITO KONDO E MAGNETISMO EM ESTRUTURAS DE PONTOS QUÂNTICOS / MANY BODY EFFECTS AND TRANSPORT PROPERTIES IN NANOSCOPIC SYSTEMS. THE KONDO EFFECT AND MAGNETISM IN QUANTUM DOT STRUCTURES
Nesta tese estudamos as propriedades de transporte de estruturas de pon- tos quânticos (PQ`s) ligados a contatos metálicos (CM). Descrevemos o formalismo dos bósons escravos através de sua aplicação ao sistema de um PQ ligado a um CM. Estudamos a nuvem Kondo (NK) dentro deste CM e desenvolvemos uma metodologia para calcular sua extensão (csi). Mostram
Publicado em: 2010
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3. Classical charge oscillations in nanoscopic systems
Uma única carga confinada ao longo do eixo de um nanocilindro, que possui uma carga de sinal contrário, e duas cargas iguais livres em um fino nano-anel condutor são exemplos de sistemas que podem oscilar com frequências na região de THz. A energia potencial obtida para o último caso pode ser generalizado para n cargas iguais (n > 2). Mostra-se que as
Revista Brasileira de Ensino de Física. Publicado em: 2009-06
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4. PROPRIEDADES DE TRANSPORTE DE SISTEMAS NANOSCÓPICOS: ÁTOMOS E MOLÉCULAS / TRANSPORT PROPERTIES OF NANOSCOPIC SYSTEMS: ATOMS AND MOLECULES
In this work we study the electronic transport in atomic and molecular structures. By using the Green´s function method, we address the problem of the electron-electron and electron-phonon interactions and their effects on the conductance of the system. We present a detailed study of the regime where these two interactions are simultaneously important and s
Publicado em: 2007
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5. The inductive coupling with On-Chip coils / O acoplamento indutivo com bobinas On-Chip
The quantum Hall effect (QHE) remains the target of an immense research effort twenty six years after its discovery. In fact this phenomenon has been a source of fundamental questions. Among the open problems in the field is the spatial distribution of the electric current in the quantum Hall effect. This question has been in debate since its discovery. Some
Publicado em: 2007
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6. 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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7. Espectroscopia de tunelamento em sistemas nanoscopicos de transporte balistico
In this work we discuss the ballistic transport properties of non-interacting electrons in confined nanoscopic system, where the sample boundaries and a controllable impurity repulsive, such as the one induced by scanning a Atomic Force Microscope tip or using split gates technique are the only source of electron sacttering. Two quantum scenary are studied:
Publicado em: 2003