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arXiv · 2401.02128

Correlated sensing with a solid-state quantum multi-sensor system for atomic-scale structural analysis

Abstract

Developing superior quantum sensing strategies ranging from ultra-high precision measurement to complex structural analysis is at the heart of quantum technologies. While strategies using quantum resources, such as entanglement among sensors, to enhance the sensing precision have been abundantly demonstrated, the signal correlation among quantum sensors is rarely exploited. Here we develop a novel sensing paradigm exploiting the signal correlation among multiple quantum sensors to resolve overlapping signals from multiple targets that individual sensors can't resolve and complex structural construction struggles with. With three nitrogen-vacancy centers as a quantum electrometer system, we demonstrate this multi-sensor paradigm by resolving individual defects' fluctuating electric fields from ensemble signals. We image the three-dimensional distribution of 16 dark electronic point-defects in diamond with accuracy approaching 1.7 nm via a GPS-like localization method. Furthermore, we obtain the real-time charge dynamics of individual point defects and visualize how the dynamics induce the well-known optical spectral diffusion. The multi-sensor paradigm extends the quantum sensing toolbox and offers new possibilities for structural analysis.

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Wentao Ji, Zhaoxin Liu, Yuhang Guo, Zhihao Hu, Jingyang Zhou, Siheng Dai, Yu Chen, Pei Yu, Mengqi Wang, Kangwei Xia, Fazhan Shi, Ya Wang, Jiangfeng Du. 2024-01-04. Correlated sensing with a solid-state quantum multi-sensor system for atomic-scale structural analysis. https://arxiv.org/abs/2401.02128

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