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arXiv · 2305.05849

Measurement of non-Abelian gauge fields using multi-loop amplification

Qing-Xian Lv·Hong-Zhi Liu·Yan-Xiong Du·Lin-Qing Chen·Meng Wang·Jia-Hao Liang·Zhao-Xin Fu·Zi-Yuan Chen·Hui Yan·Shi-Liang Zhu
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Abstract

Non-Abelian gauge field (NAGF) plays a central role in understanding the geometrical and topological phenomena in physics. Here we experimentally induce a NAGF in the degenerate eigen subspace of a double-$\Lambda$ four-level atomic system. The non-Abelian nature of the gauge field is detected through the measurement of the non-commutativity of two successive evolution loops. Then we theoretically propose and experimentally demonstrate a novel scheme to measure the NAGF through multi-loop evolution and robust holonomic quantum gates. The demonstrated scheme offers the advantage of detecting the NAGF with amplification through multi-loop evolution. Our results pave the way for an experimentally-feasible approach to achieving high-resolution and high-precision measurements of the gauge fields.

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Qing-Xian Lv, Hong-Zhi Liu, Yan-Xiong Du, Lin-Qing Chen, Meng Wang, Jia-Hao Liang, Zhao-Xin Fu, Zi-Yuan Chen, Hui Yan, Shi-Liang Zhu. 2023-05-10. Measurement of non-Abelian gauge fields using multi-loop amplification. https://arxiv.org/abs/2305.05849

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