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arXiv · 1707.01441

Continuous-time quantum walk on spatially correlated noisy lattices

Matteo A. C. Rossi·Claudia Benedetti·Massimo Borrelli·Sabrina Maniscalco·Matteo G. A. Paris
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Abstract

We address memory effects and diffusive properties of a continuous-time quantum walk on a one-dimensional percolation lattice affected by spatially correlated random telegraph noise. In particular, by introducing spatially correlated time-dependent fluctuations in nearest-neighbor hopping amplitudes, we describe random domains characterized by global noise. The resulting open dynamics of the walker is then unraveled by an ensemble average over all the noise realizations. Our results show that time-dependent noise assisted by spatial correlations leads to strong memory effects in the walker dynamics and to robust diffusive behavior against the detrimental action of uncorrelated noise. We also show that spatially correlated classical noise enhances localization breaking, thus making a quantum particle spread on longer distances across the lattice.

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Matteo A. C. Rossi, Claudia Benedetti, Massimo Borrelli, Sabrina Maniscalco, Matteo G. A. Paris. 2017-10-04. Continuous-time quantum walk on spatially correlated noisy lattices. https://doi.org/10.1103/physreva.96.040301

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