Measure for the Degree of NonMarkovian Behavior of Quantum Processes in Open Systems
Abstract
We construct a general measure for the degree of nonMarkovian behavior in open quantum systems. This measure is based on the trace distance which quantifies the distinguishability of quantum states. It represents a functional of the dynamical map describing the time evolution of physical states, and can be interpreted in terms of the information flow between the open system and its environment. The measure takes on nonzero values whenever there is a flow of information from the environment back to the open system, which is the key feature of nonMarkovian dynamics.
 Publication:

Physical Review Letters
 Pub Date:
 November 2009
 DOI:
 10.1103/PhysRevLett.103.210401
 arXiv:
 arXiv:0908.0238
 Bibcode:
 2009PhRvL.103u0401B
 Keywords:

 03.65.Yz;
 03.65.Ta;
 42.50.Lc;
 Decoherence;
 open systems;
 quantum statistical methods;
 Foundations of quantum mechanics;
 measurement theory;
 Quantum fluctuations quantum noise and quantum jumps;
 Quantum Physics
 EPrint:
 4 pages, 2 figures, published version