Decoherence and the loschmidt echo

Decoherence causes entropy increase that can be quantified using, e.g., the purity [Formula presented]. When the Hamiltonian of a quantum system is perturbed, its sensitivity to such perturbation can be measured by the Loschmidt echo [Formula presented]. It is given by the squared overlap between th...

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Detalhes bibliográficos
Autores: Cucchietti, Fernando .M., Dalvit, Diego A. R., Paz, Juan Pablo, Zurek, W. H.
Tipo de documento: artigo
Estado:Versão publicada
Data de publicação:2003
País:Argentina
Recursos:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositório:CONICET Digital (CONICET)
Idioma:inglês
OAI Identifier:oai:ri.conicet.gov.ar:11336/78182
Acesso em linha:http://hdl.handle.net/11336/78182
Access Level:Acceso aberto
Palavra-chave:Decoherence
Loschmidt Echo
https://purl.org/becyt/ford/1.3
https://purl.org/becyt/ford/1
Descrição
Resumo:Decoherence causes entropy increase that can be quantified using, e.g., the purity [Formula presented]. When the Hamiltonian of a quantum system is perturbed, its sensitivity to such perturbation can be measured by the Loschmidt echo [Formula presented]. It is given by the squared overlap between the perturbed and unperturbed state. We describe the relation between the temporal behavior of [Formula presented] and the average [Formula presented]. In this way we show that the decay of the Loschmidt echo can be analyzed using tools developed in the study of decoherence. In particular, for systems with a classically chaotic Hamiltonian the decay of [Formula presented] and [Formula presented] has a regime where it is dominated by the Lyapunov exponents. © 2003 The American Physical Society.