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arXiv · 1007.0168

Can Environmental Decoherence be Reversed for an Open Quantum System in a Magnetic field ?

A. N. Mitra
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Abstract

A simple model is considered for an open system consisting of an aggregation of magnetic particles (like greigite) in the presence of a magnetic field (H), and interacting linearly with a bath of 3D harmonic oscillators. Using the Feynman-Vernon formalism, as given in Weiss (termed FVW), the time-evolved reduced density matrix (after eliminating the bath d.o.f.'s), is examined for environmental decoherence as defined in the FVW formalism. While decoherence is usually positive for most two-way couplings with the enviroment, it is found that a $three-way$ interaction involving the system plus bath plus H-field all together, can facilitate a $reversal$ of sign of this quantity! This may have implications for quantum coherence based phenomena on the origins of life.

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A. N. Mitra. 2010-07-01. Can Environmental Decoherence be Reversed for an Open Quantum System in a Magnetic field ?. https://arxiv.org/abs/1007.0168

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