English

Controlling quantum random walk with a step-dependent coin

Quantum Physics 2018-08-23 v2

Abstract

We report on the possibility of controlling quantum random walks with a step-dependent coin. The coin is characterized by a (single) rotation angle. Considering different rotation angles, one can find diverse probability distributions for this walk including: complete localization, Gaussian and asymmetric likes. In addition, we explore the entropy of walk in two contexts; for probability density distributions over position space and walker's internal degrees of freedom space (coin space). We show that entropy of position space can decrease for a step-dependent coin with the step-number, quite in contrast to a walk with step-independent coin. For entropy of coin space, a damped oscillation is found for walk with step-independent coin while for a step-dependent coin case, the behavior of entropy depends on rotation angle. In general, we demonstrate that quantum walks with simple initiatives may exhibit a quite complex and varying behavior if step-dependent coins are applied. This provides the possibility of controlling quantum random walk with a step-dependent coin.

Keywords

Cite

@article{arxiv.1803.02231,
  title  = {Controlling quantum random walk with a step-dependent coin},
  author = {S. Panahiyan and S. Fritzsche},
  journal= {arXiv preprint arXiv:1803.02231},
  year   = {2018}
}

Comments

17 pages, 9 figures

R2 v1 2026-06-23T00:43:53.685Z