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arXiv · 1707.05449

A self-guide method to search maximal Bell violation for unknown quantum states

Li-Kai Yang·Geng Chen·Wen-Hao Zhang·Xi-Xiang Peng·Shang Yu·Chuan-Feng Li·Guang-Can Guo
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Abstract

In recent decades, a great variety of researches and applications concerning Bell nonlocality have been developed with the advent of quantum information science. Providing that Bell nonlocality can be revealed by the violation of a family of Bell inequalities, finding maximal Bell violation (MBV) for unknown quantum states becomes an important and inevitable task during Bell experiments. In this paper we introduce a self-guide method to find MBVs for unknown states using a stochastic gradient ascent algorithm (SGA), by parameterizing the corresponding Bell operators. For all the investigated systems (2-qubit, 3-qubit and 2-qutrit), this method can ascertain the MBV accurately within 100 iterations. Moreover, SGA exhibits significant superiority in efficiency, robustness and versatility compared to other possible methods.

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Li-Kai Yang, Geng Chen, Wen-Hao Zhang, Xi-Xiang Peng, Shang Yu, Chuan-Feng Li, Guang-Can Guo. 2017-07-18. A self-guide method to search maximal Bell violation for unknown quantum states. https://doi.org/10.1103/physreva.96.052310

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