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arXiv · 2608.08130

Preserving Heisenberg-Limited Metrological Information during Storage via Correlated-Noise Correction

Hang Xu·Xue-Ke Song·Jingzheng Huang·Tailong Xiao·Guihua Zeng
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Abstract

Quantum error correction has become an indispensable tool for restoring Heisenberg-limited precision in noisy quantum metrology. Existing protocols, however, almost exclusively focus on correcting noise during the signal-encoding stage and implicitly assume that the probe is measured immediately after sensing. In many quantum information processing tasks, the encoded probe must instead be stored before subsequent quantum operations, during which environmental noise can significantly degrade the accumulated metrological information. Here, we propose a correlated-noise correction (CNC) protocol for protecting quantum probes during the storage stage. By correlating probe errors with auxiliary qubits through fixed two-body entangling gates, memory errors are converted into measurable syndromes that are extracted only once after storage. We show that the protocol naturally extends from single-qubit to multi-qubit probes and protects the stored quantum Fisher information against dephasing, bit-flip, and amplitude-damping noise. Furthermore, we demonstrate that preserving the quantum Fisher information does not necessarily require restoring the entire quantum state when the probe is measured immediately after storage, whereas full state recovery becomes essential for subsequent rounds of quantum signal processing. Our results establish correlated-noise correction as a practical framework for protecting metrological information during quantum memory and provide a useful building block for sensing-enabled quantum information processing.

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Hang Xu, Xue-Ke Song, Jingzheng Huang, Tailong Xiao, Guihua Zeng. 2026-08-08. Preserving Heisenberg-Limited Metrological Information during Storage via Correlated-Noise Correction. https://arxiv.org/abs/2608.08130

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