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arXiv · 2308.04042

Nonlinear time-reversal interferometry with arbitrary quadratic collective-spin interaction

Zhiyao Hu·Qixian Li·Xuanchen Zhang·He-bin Zhang·Long-Gang Huang·Yong-Chun Liu
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Abstract

Atomic nonlinear interferometry has wide applications in quantum metrology and quantum information science. Here we propose a nonlinear time-reversal interferometry scheme with high robustness and metrological gain based on the spin squeezing generated by arbitrary quadratic collective-spin interaction, which could be described by the Lipkin-Meshkov-Glick (LMG) model. We optimize the squeezing process, encoding process, and anti-squeezing process, finding that the two particular cases of the LMG model, one-axis twisting and two-axis twisting outperform in robustness and precision, respectively. Moreover, we propose a Floquet driving method to realize equivalent time reverse in the atomic system, which leads to high performance in precision, robustness, and operability. Our study sets a benchmark in achieving high precision and robustness in atomic nonlinear interferometry.

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Zhiyao Hu, Qixian Li, Xuanchen Zhang, He-bin Zhang, Long-Gang Huang, Yong-Chun Liu. 2023-08-08. Nonlinear time-reversal interferometry with arbitrary quadratic collective-spin interaction. https://arxiv.org/abs/2308.04042

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