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Showing 1 to 6 of 6 for “"Kondo model"”.
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Path integral methods for the large-N Kondo model
A path integral formulation of the SU(N) Kondo model is explored as a possible theoretical tool for studying generalizations of the model, such as the Kondo lattice, which are difficult to study by other means. Saddle point approximations to the path integral lead to an expansion in powers of 1/N. …
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Decoherence effects in nonequilibrium transport through mesoscopic systems
… are developed and applied to two different model systems, and the results are analysed with a special focus on the role of relaxation and decoherence rates. First, transport through a quantum wire which is coupled to a ferromagnetic spin chain is investigated using a calculation within the …
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Método atômico para o modelo de Anderson em presença de um campo magnético externo.
… the atomic method (AM) for the Anderson impurity model under an external magnetic field. The Green s functions (GF) representing the exact solution of the impurity problem is written in terms of an effective cumulant, that in the atomic method is replaced by the atomic cumulant obtained from the …
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Studies on the effect of noise in boundary quantum phase transitions
… systems, including the dissipative two impurity Kondo, two channel Kondo, resonant level, and Anderson models.</p><p>To begin with, the effect of dissipation in two impurity Kondo model has been explored and we find that the presence of dissipation restores the quantum phase transition by …
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Phase diagram for the S equals one-half and J equals three-halves Kondo lattice model
A Kondo lattice Hamiltonian for arbitrary total angular momentum J is formulated using a pseudofermion representation and without addition of RKKY interaction terms. An Hartree-Fock treatment is applied, and both variational and Green's function methods are used to calculate physical quantities …
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Quantum transport through single molecules
… through single molecules. Therefore transport models are developed that take into account the special magnetic, electronic and electro-chemical properties of the molecules of interest. One advantage of this approach is that model parameters can be fixed by ab-initio calculations which allows a …