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arXiv · 2206.11185

An Improved Sample Complexity Lower Bound for (Fidelity) Quantum State Tomography

Henry Yuen
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Abstract

We show that $\Omega(rd/\epsilon)$ copies of an unknown rank-$r$, dimension-$d$ quantum mixed state are necessary in order to learn a classical description with $1 - \epsilon$ fidelity. This improves upon the tomography lower bounds obtained by Haah, et al. and Wright (when closeness is measured with respect to the fidelity function).

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Henry Yuen. 2022-06-22. An Improved Sample Complexity Lower Bound for (Fidelity) Quantum State Tomography. https://doi.org/10.22331/q-2023-01-03-890

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