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arXiv:2606.31827

Correlation-enhanced metrology from scrambling dynamics in a solid-state spin system

Yu-Chen Li, Shengyu Zhang, Ze Wu, Haochuan Yin, Liqiang Zhao, Xiaoxue An, Jiaxi Cui, Dieter Suter, Xinhua Peng

quant-phSubmitted Jun 30, 2026• Announced Jul 1, 2026• 0 citations
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Abstract

Quantum information scrambling, the dispersal of local information into many-body degrees of freedom, provides a powerful mechanism for generating large-scale correlations and entanglement essential for quantum-enhanced metrology. However, experimentally verifying such quantum-enhanced metrology remains a demanding task. Here, we correlate thousands of spins by engineering chaotic scrambling dynamics in a solid-state nuclear spin system. By leveraging the newly developed scramblon theory, we reveal exponential scaling in both the quantum Fisher information and the signal response to a phase shift. The signal response achieves a correlation-enabled enhancement of $33(2)$ dB over uncorrelated spins. After accounting for signal loss due to imperfect time reversal in the readout stage, we obtain a total metrological gain of 18(1) dB with a phase sensitivity of 40(3) ${\mathrm{μrad}}$. Our results bridge quantum chaos with practical quantum metrology, establishing reversible scrambling dynamics as a powerful resource for precision measurements.

Comments
8 pages, 3 figures, supplementary material 9 pages, 3 figures

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