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arXiv · 2309.00177

Enhanced quantum sensing with amplification and deamplification

Min Jiang·Yushu Qin·Yuanhong Wang·Ying Huang·Xinhua Peng·Dmitry Budker
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Abstract

Quantum sensing is a fundamental building block of modern technology that employs quantum resources and creates new opportunities for precision measurements. However, previous methods usually have a common assumption that detection noise levels should be below the intrinsic sensitivity provided by quantum resources. Here we report the first demonstration of Fano resonance between coupled alkali-metal and noble gases through rapid spin-exchange collisions. The Fano resonance gives rise to two intriguing phenomena: spin amplification and deamplification, which serve as crucial resources for enhanced sensing. Further we develop a novel scheme of quantum sensing enhanced by amplification and deamplification, with relaxed requirements on the detection noise. The coupled systems of alkali-metal and noble gases act as amplifiers or de-amplifiers, enabling to extract small signals above the detection noise before final detection. We demonstrate magnetic-field measurement about 54 decibels below the photon-shot noise, which outperforms the state-of-the-art squeezed-light technology and realizes femtotesla-level sensitivity. Our work opens new avenues to applications in searches for ultralight dark matter with sensitivity well beyond the supernova-observation constraints.

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Min Jiang, Yushu Qin, Yuanhong Wang, Ying Huang, Xinhua Peng, Dmitry Budker. 2023-09-01. Enhanced quantum sensing with amplification and deamplification. https://arxiv.org/abs/2309.00177

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