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arXiv · 2211.10350

Magic of Random Matrix Product States

Liyuan Chen·Roy J. Garcia·Kaifeng Bu·Arthur Jaffe
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Abstract

Magic, or nonstabilizerness, characterizes how far away a state is from the stabilizer states, making it an important resource in quantum computing, under the formalism of the Gotteman-Knill theorem. In this paper, we study the magic of the $1$-dimensional Random Matrix Product States (RMPSs) using the $L_{1}$-norm measure. We firstly relate the $L_{1}$-norm to the $L_{4}$-norm. We then employ a unitary $4$-design to map the $L_{4}$-norm to a $24$-component statistical physics model. By evaluating partition functions of the model, we obtain a lower bound on the expectation values of the $L_{1}$-norm. This bound grows exponentially with respect to the qudit number $n$, indicating that the $1$D RMPS is highly magical. Our numerical results confirm that the magic grows exponentially in the qubit case.

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Liyuan Chen, Roy J. Garcia, Kaifeng Bu, Arthur Jaffe. 2022-11-18. Magic of Random Matrix Product States. https://doi.org/10.1103/physrevb.109.174207

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