arXiv:1209.5059

Quantum random walks and thermalisation II

Alexander C. R. Belton

Published Sep 23, 2012• 0 citations

Abstract

A convergence theorem is obtained for quantum random walks with particles in an arbitrary normal state. This result unifies and extends previous work on repeated-interactions models, including that of the author (2010, J. London Math. Soc. (2) 81, 412-434; 2010, Comm. Math. Phys. 300, 317-329). When the random-walk generator acts by ampliation and multiplication or conjugation by a unitary operator, necessary and sufficient conditions are given for the quantum stochastic cocycle which arises in the limit to be driven by an isometric, co-isometric or unitary process.

DOI: 10.48550/arxiv.1209.5059

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