Two Impurity Anderson Model
Mostrando 1-7 de 7 artigos, teses e dissertações.
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1. Efeito capacitivo em um sistema de dois pontos quânticos acoplados no regime Kondo
In this work we study a system composed by two quantum dots coupled to each other and one of each coupled to two metallic leads. Theoretically the system is described by a generalized two-impurity Anderson model. In this Hamiltonian we include both intraand inter-site electron-electron interaction, where the former is due to the confinement of electrons in a
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 22/07/2011
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2. Electronic transport through a single-wall carbon nanotube with a magnetic impurity
We are interested in studying the transport properties of metallic single-wall carbon nanotubes (SWCNTs) with isolated magnetic impurities. We consider a metallic zigzag SWCNT in the form of an infinitely long cylinder of diameter D, connected by two metallic electrodes under a bias voltage $E$, with a magnetic impurity located on its surface. To describe th
Brazilian Journal of Physics. Publicado em: 2006-06
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3. Electronic transport through a quantum wire with a side-coupled quantum dot
We describe the Kondo resonance in quantum dots employing the atomic model. We calculate approximate Green's functions of the impurity Anderson model employing the exact solution of the system with a conduction band with zero width, and we use the completeness condition to choose the position of that band. At low temperatures, there are two solutions close t
Brazilian Journal of Physics. Publicado em: 2006-06
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4. Modelo de Anderson para duas impurezas : Metodo dos campos efetivos / The two-impurity Anderson model : an effective medium approach
O Hamiltoniano do modelo de Anderson para duas impurezas é estudado via um desacoplamento das funções de Green. Neste caso resulta ser equivalente a aproximação de potencial coerente (CPA) que também, neste caso, coincide com a aproximação Hubbard-I. Consideram-se todos os termos de interação impureza-impureza, tanto os denominados termos de um cor
Publicado em: 2004
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5. Numerical renormalization group and the two-impurity problem / O grupo de renormalização numérico e o problema de duas impurezas
Neste trabalho é calculada a contribuição de duas impurezas magnéticas ao calor específico e à entropia de um metal através do grupo de renormalização numérico. Tal sistema físico foi descrito pelo modelo Kondo de duas impurezas, onde cada impureza é simplesmente um momento magnético associado a um spin S=1/2, e representa um elétron ocupando u
Publicado em: 2004
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6. Efeitos de temperatura e de interação finita em sistemas desordenados correlacionados
The main goal of this work is to study the role of disorder in strongly correlated systems, where the electron-electron interaction is comparable to or dominates over the electron kinetic energy. Keeping this in mind, we solve the Hubbard model and the Anderson lattice model in the presence of disorder. The main theory in which our work is based is the Dynam
Publicado em: 2003
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7. Numerical Renormalization-group Computation of Specific Heats. / Calor específico do modelo de Anderson de uma impureza por grupo de renormalização numérico
The specific heat and the entropy of the one-impurity symmetric Anderson Model are calculated using the Numerical Renormalization Group (NRG). The heart of the method is the logarithmic discretization of the metal conduction band where the impurity is coupled. However, this discretization, inherent in the method, introduces oscillations in the thermodynamica
Publicado em: 1995