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arXiv · 2308.08113

Enhanced super-Heisenberg scaling precision by nonlinear coupling and postselection

Lupei Qin·Jialin Li·Yazhi Niu·Xin-Qi Li
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Abstract

In quantum precision metrology, the famous result of Heisenberg limit scaling as $1/N$ (with $N$ the number of probes) can be surpassed by considering nonlinear coupling measurement. In this work, we consider the most practice-relevant quadratic nonlinear coupling and show that the metrological precision can be enhanced from the $1/N^{\frac{3}{2}}$ super-Heisenberg scaling to $1/N^2$, by simply employing a pre- and post-selection (PPS) technique, but not using any expensive quantum resources such as quantum entangled state of probes.

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Lupei Qin, Jialin Li, Yazhi Niu, Xin-Qi Li. 2023-08-16. Enhanced super-Heisenberg scaling precision by nonlinear coupling and postselection. https://arxiv.org/abs/2308.08113

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