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Analytical expression for variance of homogeneous-position quantum walk with decoherent position

  • Mostafa Annabestani
Article
  • 39 Downloads

Abstract

We have derived an analytical expression for variance of homogeneous-position decoherent quantum walk with general form of noise on its position, and have shown that, while the quadratic (\(t^2\)) term of variance never changes by position decoherency, the linear term (t) does and always increases the variance. We study the walker with ability to tunnel out to d nearest neighbors as an example and compare our result with former studies. We also show that, although our expression has been derived for asymptotic case, the rapid decay of time-dependent terms causes the expressions to be correct with a good accuracy even after dozens of steps.

Keywords

Quantum walk Decoherency Variance Coin-position entanglement 

Notes

Acknowledgements

I would sincerely like to thank Maryam Boozarjmehr from the Australian National University, for her accurate reading and editing the manuscript.

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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2017

Authors and Affiliations

  1. 1.Faculty of PhysicsShahrood University of TechnologyShahroodIran

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