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arXiv · 2112.02846

Decoherence on Staggered Quantum Walks

R. A. M. Santos·F. L. Marquezino
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Abstract

Decoherence phenomenon has been widely studied in different types of quantum walks. In this work we show how to model decoherence inspired by percolation on staggered quantum walks. Two models of unitary noise are described: breaking polygons and breaking vertices. The evolution operators subject to these noises are obtained and the equivalence to the coined quantum walk model is presented. Further, we numerically analyze the effect of these decoherence models on the two-dimensional grid of $4$-cliques. We examine how these perturbations affect the quantum walk based search algorithm in this graph and how expanding the tessellations intersection can make it more robust against decoherence.

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R. A. M. Santos, F. L. Marquezino. 2021-12-06. Decoherence on Staggered Quantum Walks. https://doi.org/10.1103/physreva.105.032452

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