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arXiv · 1908.04124

Lazy Open Quantum Walks

Garreth Kemp·Ilya Sinayskiy·Francesco Petruccione
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Abstract

Open quantum walks (OQWs) describe a quantum walker on an underlying graph whose dynamics is purely driven by dissipation and decoherence. Mathematically, they are formulated as completely positive trace preserving (CPTP) maps on the space of density matrices for the walker on the graph. Any microscopically derived OQW must include the possibility of remaining on the same site on the graph when the map is applied. We extend the CPTP map to describe a lazy OQW. We derive a central limit theorem for lazy OQWs on a $d$-dimensional lattice, where the distribution converges to a Gaussian. We show that the properties of this Gaussian computed using conventional methods agree with the general formulas derived from our central limit theorem.

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Garreth Kemp, Ilya Sinayskiy, Francesco Petruccione. 2019-08-12. Lazy Open Quantum Walks. https://doi.org/10.1103/physreva.102.012220

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