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arXiv · 2409.14048

Super-Heisenberg scaling in a triple point criticality

Jia-Ming Cheng·Yong-Chang Zhang·Xiang-Fa Zhou·Zheng-Wei Zhou
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Abstract

We investigate quantum-enhanced metrology in a triple point criticality and discover that quantum criticality can not always enhance measuring precision. We have developed suitable adiabatic evolution protocols approaching a final point around the triple point to effectively restrain excitations, which could accelerate the adiabatic evolutions and lead to an exponential super-Heisenberg scaling. This scaling behavior is quite valuable in practical parameter estimating experiments with limited coherence time. The super-Heisenberg scaling will degrade into a sub-Heisenberg scaling if the adiabatic parameter modulations adopted can not reduce excitations and weaken the slowing down effect. Additionally, a feasible experimental scheme is also suggested to achieve the anticipated exponential super-Heisenberg scaling. Our findings strongly indicate that criticality-enhanced metrology can indeed significantly enhance measuring precision to a super-Heisenberg scaling when combining a triple point and beneficial parameter modulations in the adiabatic evolution, which will be conducive to the exploration of other super-Heisenberg scaling and their applications.

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Jia-Ming Cheng, Yong-Chang Zhang, Xiang-Fa Zhou, Zheng-Wei Zhou. 2024-09-21. Super-Heisenberg scaling in a triple point criticality. https://arxiv.org/abs/2409.14048

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