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Role of many-body entanglement in decoherence processes

Helen McAneney·Jinhyoung Lee·M. S. Kim
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Abstract

A pure state decoheres into a mixed state as it entangles with an environment. When an entangled two-mode system is embedded in a thermal environment, however, each mode may not be entangled with its environment by their simple linear interaction. We consider an exactly solvable model to study the dynamics of a total system, which is composed of an entangled two-mode system and a thermal environment, and also an array of infinite beam splitters. It is shown that many-body entanglement of the system and the environment plays a crucial role in the process of disentangling the system.

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Helen McAneney, Jinhyoung Lee, M. S. Kim. 2002-10-16. Role of many-body entanglement in decoherence processes. https://doi.org/10.1103/physreva.68.063814

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