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Collisional decoherence reexamined

Klaus Hornberger·John E. Sipe
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Abstract

We re-derive the quantum master equation for the decoherence of a massive Brownian particle due to collisions with the lighter particles from a thermal environment. Our careful treatment avoids the occurrence of squares of Dirac delta functions. It leads to a decoherence rate which is smaller by a factor of 2 pi compared to previous findings. This result, which is in agreement with recent experiments, is confirmed by both a physical analysis of the problem and by a perturbative calculation in the weak coupling limit.

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Klaus Hornberger, John E. Sipe. 2003-05-16. Collisional decoherence reexamined. https://doi.org/10.1103/physreva.68.012105

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