To employ a quantum device, the performance of the quantum gates in the device needs to be evaluated first. Since the dimensionality of a quantum gate grows exponentially with the number of qubits, evaluating the performance of a quantum gate is a challenging task. Recently, a scheme called quantum gate verification (QGV) has been proposed, which can verifies quantum gates with near-optimal efficiency. In this paper, we implement a proof-of-principle optical experiment to demonstrate this QGV scheme. We show that for a single-qubit quantum gate, only ∼300 samples are needed to confirm the fidelity of the quantum gate to be at least 97% with a 99% confidence level using the QGV method, whereas, at least ∼3000 samples are needed to achieve the same result using the standard quantum process tomography method. The QGV method validated by this paper has the potential to be widely used for the evaluation of quantum devices in various quantum information applications.
@article{arxiv.2107.13466,
title = {Proof-of-principle experimental demonstration of quantum gate verification},
author = {Maolin Luo and Xiaoqian Zhang and Xiaoqi Zhou},
journal= {arXiv preprint arXiv:2107.13466},
year = {2022}
}