arXiv:1011.4117 · Physical Review A

Information flow, non-Markovianity, and geometric phases

S. L. Wu, X. L. Huang, L. C. Wang, X. X. Yi

Published Nov 15, 2010• 15 citations

Abstract

Geometric phases and information flows of a two-level system coupled to its environment are calculated and analyzed. The information flow is defined as a cumulant of changes in trace distance between two quantum states, which is similar to the measure for non-Markovianity given by Breuer. We obtain an analytic relation between the geometric phase and the information flow for pure initial states, and a numerical result for mixed initial states. The geometric phase behaves differently depending on whether there are information flows back to the two-level system from its environment.

DOI: 10.1103/physreva.82.052111

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