Decoherence as a Signature of an Excited State Quantum Phase Transition in Two Level Boson Systems

We analyze the decoherence induced on a single qubit by the interaction with a two-level boson system with critical internal dynamics. We explore how the decoherence process is affected by the presence of quantum phase transitions in the environment. We conclude that the dynamics of the qubit change...

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Detalles Bibliográficos
Autores: García Ramos, J. E., Arias, J. M., Dukelsky, J., Pérez Fernández, P., Relaño Pérez, Armando
Tipo de recurso: capítulo de libro
Fecha de publicación:2009
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/53487
Acceso en línea:https://hdl.handle.net/20.500.14352/53487
Access Level:acceso abierto
Palabra clave:536
Quantum decoherence
Quatum phase transition
Excited state quatum phase transition
Física (Física)
22 Física
Descripción
Sumario:We analyze the decoherence induced on a single qubit by the interaction with a two-level boson system with critical internal dynamics. We explore how the decoherence process is affected by the presence of quantum phase transitions in the environment. We conclude that the dynamics of the qubit changes dramatically when the environment passes through a continuous excited state quantum phase transition. If the system-environment coupling energy equals the energy at which the environment has a critical behavior, the decoherence induced on the qubit is maximal and the fidelity tends to zero with finite size scaling obeying a power-law.