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arXiv · 2010.10592

Quantum information spreading in a disordered quantum walk

Farzam Nosrati·Alessandro Laneve·Mahshid Khazaei Shadfar·Andrea Geraldi·Kobra Mahdavipour·Federico Pegoraro·Paolo Mataloni·Rosario Lo Franco
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Abstract

We design a quantum probing protocol using Quantum Walks to investigate the Quantum Information spreading pattern. We employ Quantum Fisher Information, as a figure of merit, to quantify extractable information about an unknown parameter encoded within the Quantum Walk evolution. Although the approach is universal, we focus on the coherent static and dynamic disorder to investigate anomalous and classical transport as well as Anderson localization. Our results show that a Quantum Walk can be considered as a readout device of information about defects and perturbations occurring in complex networks, both classical and quantum.

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Farzam Nosrati, Alessandro Laneve, Mahshid Khazaei Shadfar, Andrea Geraldi, Kobra Mahdavipour, Federico Pegoraro, Paolo Mataloni, Rosario Lo Franco. 2020-10-20. Quantum information spreading in a disordered quantum walk. https://doi.org/10.1364/josab.431752

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