arXiv:quant-ph/0312099 · Physical Review A

Disentanglement by dissipative open system dynamics

Peter J. Dodd

Published May 12, 2004• 40 citations

Abstract

This paper investigates disentanglement as a result of evolution according to a class of master equations which include dissipation and interparticle interactions. Generalizing an earlier result of Di\'osi, the time taken for complete disentanglement iscalculated (i.e., for disentanglement from any other system). The dynamics of two harmonically coupled oscillators is solved in order to study the competing effects of environmental noise and interparticle coupling on disentanglement. An argument based on separability conditions for Gaussian states is used to arrive at a set of conditions on the couplings sufficient for all initial states to disentangle for good after a finite time.

DOI: 10.1103/physreva.69.052106

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