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arXiv · 2102.07079

Quantum metrology with precision reaching beyond-$1/N$ scaling through $N$-probe entanglement generating interactions

Xing Deng·Shou-Long Chen·Mao Zhang·Xiao-Fan Xu·Jing Liu·Zhi Gao·Xiao-Chun Duan·Min-Kang Zhou·Lushuai Cao·Zhong-Kun Hu
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Abstract

Nonlinear interactions are recognized as potential resources for quantum metrology, facilitating parameter estimation precisions that scale as the exponential Heisenberg limit of $2^{-N}$. We explore such nonlinearity and propose an associated quantum measurement scenario based on the nonlinear interaction of $N$-probe entanglement generating form. This scenario provides an enhanced precision scaling of $D^{-N}/(N-1)!$ with $D > 2$ a tunable parameter. In addition, it can be readily implemented in a variety of experimental platforms and applied to measurements of a wide range of quantities, including local gravitational acceleration $g$, magnetic field, and its higher-order gradients.

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Xing Deng, Shou-Long Chen, Mao Zhang, Xiao-Fan Xu, Jing Liu, Zhi Gao, Xiao-Chun Duan, Min-Kang Zhou, Lushuai Cao, Zhong-Kun Hu. 2021-02-14. Quantum metrology with precision reaching beyond-$1/N$ scaling through $N$-probe entanglement generating interactions. https://doi.org/10.1103/physreva.104.012607

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