English

Properties of quantum stochastic walks from the asymptotic scaling exponent

Quantum Physics 2018-03-21 v2

Abstract

This work focuses on the study of quantum stochastic walks, which are a generalization of coherent, i. e. unitary quantum walks. Our main goal is to present a measure of a coherence of the walk. To this end, we utilize the asymptotic scaling exponent of the second moment of the walk i. e. of the mean squared distance covered by a walk. As the quantum stochastic walk model encompasses both classical random walks and quantum walks, we are interested how the continuous change from one regime to the other influences the asymptotic scaling exponent. Moreover this model allows for behavior which is not found in any of the previously mentioned model -- the model with global dissipation. We derive the probability distribution for the walker, and determine the asymptotic scaling exponent analytically, showing that ballistic regime of the walk is maintained even at large dissipation strength.

Keywords

Cite

@article{arxiv.1611.01349,
  title  = {Properties of quantum stochastic walks from the asymptotic scaling exponent},
  author = {Krzysztof Domino and Adam Glos and Mateusz Ostaszewski and Łukasz Pawela and Przemysław Sadowski},
  journal= {arXiv preprint arXiv:1611.01349},
  year   = {2018}
}