Efficient Learning of Quantum States Prepared With Few Non-Clifford Gates II: Single-Copy Measurements

Sabee Grewal; Vishnu Iyer; William Kretschmer; Daniel Liang

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arXiv · 2308.07175

Efficient Learning of Quantum States Prepared With Few Non-Clifford Gates II: Single-Copy Measurements

Sabee Grewal·Vishnu Iyer·William Kretschmer·Daniel Liang

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Abstract

Recent work has shown that $n$-qubit quantum states output by circuits with at most $t$ single-qubit non-Clifford gates can be learned to trace distance $\epsilon$ using $\mathsf{poly}(n,2^t,1/\epsilon)$ time and samples. All prior algorithms achieving this runtime use entangled measurements across two copies of the input state. In this work, we give a similarly efficient algorithm that learns the same class of states using only single-copy measurements.

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Sabee Grewal, Vishnu Iyer, William Kretschmer, Daniel Liang. 2023-08-14. Efficient Learning of Quantum States Prepared With Few Non-Clifford Gates II: Single-Copy Measurements. https://arxiv.org/abs/2308.07175

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