# Quantum advantages for Pauli channel estimation

@article{Chen2022QuantumAF,
title={Quantum advantages for Pauli channel estimation},
author={Senrui Chen and Sisi Zhou and Alireza Seif and Liang Jiang},
journal={Physical Review A},
year={2022}
}
• Published 19 August 2021
• Computer Science
• Physical Review A
We show that entangled measurements provide an exponential advantage in sample complexity for Pauli channel estimation, which is both a fundamental problem and a practically important subroutine for benchmarking near-term quantum devices. The specific task we consider is to simultaneously learn all the eigenvalues of an n-qubit Pauli channel to ±ε precision. We give an estimation protocol with an n-qubit ancilla that succeeds with high probability using only O(n/ε2) copies of the Pauli channel…
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