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arXiv · 0808.3403

Reexamination of decoherence in quantum walks on the hypercube

Frederick W. Strauch
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Abstract

The effect of decoherence on the continuous-time quantum walk on the hypercube is revisited. Previously, an exact solution was found for a decoherence model that preserved the effective tensor-product form of the dynamics. Here a new model is presented, inspired by perfect quantum state transfer in qubit networks. A perturbative solution is found for the dynamics of this model which is not of a tensor-product form. In contrast to previous results, the hitting probability has a lower bound that is independent of the hypercube dimension.

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Frederick W. Strauch. 2008-12-12. Reexamination of decoherence in quantum walks on the hypercube. https://doi.org/10.1103/physreva.79.032319

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