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Decoherence induced by a phase-damping reservoir

R. M. Angelo·E. S. Cardoso·K. Furuya
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Abstract

A phase damping reservoir composed by $N$-bosons coupled to a system of interest through a cross-Kerr interaction is proposed and its effects on quantum superpo sitions are investigated. By means of analytical calculations we show that: i-) the reservoir induces a Gaussian decay of quantum coherences, and ii-) the inher ent incommensurate character of the spectral distribution yields irreversibility . A state-independent decoherence time and a master equation are both derived an alytically. These results, which have been extended for the thermodynamic limit, show that nondissipative decoherence can be suitably contemplated within the EI D approach. Finally, it is shown that the same mechanism yielding decoherence ar e also responsible for inducing dynamical disentanglement.

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R. M. Angelo, E. S. Cardoso, K. Furuya. 2006-06-16. Decoherence induced by a phase-damping reservoir. https://doi.org/10.1103/physreva.73.062107

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