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arXiv · 1711.10878

Quantum State Tomography for Generic Pure States

Shilin Huang·Jianxin Chen·Youning Li·Bei Zeng
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Abstract

We show that a generic $N$-qudit pure quantum state is uniquely determined by only $2$ of its $\lceil\frac{N+1}{2}\rceil$-particle reduced density matrices. Therefore we give a method to uniquely determine a generic $N$-qudit pure state of dimension $D=d^N$ with $O(D)$ local measurements, which is an improvement comparing with the previous known approach using $O(D\log^2 D)$ or $O(D\log D)$ measurements.

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Shilin Huang, Jianxin Chen, Youning Li, Bei Zeng. 2018-01-13. Quantum State Tomography for Generic Pure States. https://arxiv.org/abs/1711.10878

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