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arXiv · 0908.0019

Driving quantum walk spreading with the coin operator

Alejandro Romanelli
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Abstract

We generalize the discrete quantum walk on the line using a time dependent unitary coin operator. We find an analytical relation between the long-time behaviors of the standard deviation and the coin operator. Selecting the coin time sequence allows to obtain a variety of predetermined asymptotic wave-function spreadings: ballistic, sub-ballistic, diffusive, sub-diffusive and localized.

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Alejandro Romanelli. 2009-07-31. Driving quantum walk spreading with the coin operator. https://doi.org/10.1103/physreva.80.042332

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