Tese de Doutorado
Transição de fase quântica em um hamiltoniano efetivo de três modos para bósons interagentes
Fecha
2018-07-13Autor
Heliques Mesquita Frazao
Institución
Resumen
In this work, we study an effective three-mode Hamiltonian describing interacting bosons. These bosons can be considered as exciton-polaritons in a semiconductor microcavity at the magic angle or cold atoms optically trapped in a triple-well potential with a population imbalance conservation. We observe that the quantum properties of the spectrum characterize a quantum phase transition. We realize a thermodynamic limit of the Hamiltonian and we study the classical properties of the phase space. We observe a close analogy between quantum and classical properties: an inflection point (a level approximation) in spectrum corresponds to a separatrix (a trajectory that separates librations and rotations) in phase space. This analogy allows us to characterize the system phases, the order of the transition, and also to construct a phase diagram.