Um modelo esquemático e um modelo realistico para tunelamento coerente em poco duplo

We present two examples of tunneling in double well potentials. Therst is a study of the localization in a dissipative one-particle system bymeans of an analogy with a spin-1/2 system in a uniform magnetic eld.The second example is an investigation of the tunneling process of a Bose-Einstein Condens...

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Detalles Bibliográficos
Autor: Gabriela Barreto Lemos
Tipo de recurso: tesis de maestría
Estado:Versión publicada
Fecha de publicación:2006
País:Brasil
Institución:Universidade Federal de Minas Gerais (UFMG)
Repositorio:Repositório Institucional da UFMG
Idioma:portugués
OAI Identifier:oai:repositorio.ufmg.br:1843/IACO-6W9SBQ
Acceso en línea:http://hdl.handle.net/1843/IACO-6W9SBQ
Access Level:acceso abierto
Palabra clave:tunelamento coerente em poco duplo
Tunelamento (Física)
Física
Descripción
Sumario:We present two examples of tunneling in double well potentials. Therst is a study of the localization in a dissipative one-particle system bymeans of an analogy with a spin-1/2 system in a uniform magnetic eld.The second example is an investigation of the tunneling process of a Bose-Einstein Condensate in a double well potential from the point of view ofa many body Hamiltonian. Although the two-mode model for the processis not realistic for large enough number of particles (N 200), for certaininitial conditions, it points out a completely dierent explanation for thenon-observation of tunneling from that given in Michael Albiez et al, Phys.Rev. Lett. 95, 010402 (2005). We observe a \phase transition" related to spectral properties of the Hamiltonian and the initial conditions which, for large enough initial population imbalance, presents occupation probabilitiesconcentrated in doublets.