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arXiv · 0910.5397

Control by quantum dynamics on graphs

Chris Godsil·Simone Severini
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Abstract

We address the study of controllability of a closed quantum system whose dynamical Lie algebra is generated by adjacency matrices of graphs. We characterize a large family of graphs that renders a system controllable. The key property is a novel graph-theoretic feature consisting of a particularly disordered cycle structure. Disregarding efficiency of control functions, but choosing subfamilies of sparse graphs, the results translate into continuous-time quantum walks for universal computation.

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Chris Godsil, Simone Severini. 2012-01-07. Control by quantum dynamics on graphs. https://doi.org/10.1103/physreva.81.052316

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