近日，中国科学技术大学杜江峰团队揭示了纠缠增强纳米级单自旋传感。该项研究成果发表在2025年11月26日出版的《自然》杂志上。

探测单个自旋（包括稳定态与亚稳态）是量子传感领域的基础性挑战，其应用广泛覆盖凝聚态物理、量子化学及单分子磁共振成像领域。尽管金刚石中的氮-空位（NV）中心已发展为强大的纳米级传感器，但其单自旋检测性能仍受制于显著的环境噪声和有限的传感体积。

研究组提出并验证了一种基于纠缠增强的传感协议，通过策略性利用纠缠NV对突破上述限制。该方法在常温条件下实现了比单NV中心高3.4倍的灵敏度和1.6倍的空间分辨率提升。协议通过精心设计的纠缠态，利用量子干涉放大目标自旋信号的同时抑制环境噪声。关键进展在于将该技术拓展至亚稳态单自旋动力学的解析，通过识别依赖自旋态的耦合强度，直接观测到不同自旋态间的随机跃迁。这种双重功能使得静态与动态自旋物种的同步检测成为可能，为复杂量子系统的表征提供了新途径。该研究的性能指标确立了纠缠增强传感作为量子材料与界面原子级表征可行技术路径的地位。

附：英文原文

Title: Entanglement-enhanced nanoscale single-spin sensing

Author: Zhou, Xu, Wang, Mengqi, Ye, Xiangyu, Sun, Haoyu, Guo, Yuhang, Han, Shuo, Chai, Zihua, Ji, Wentao, Xia, Kangwei, Shi, Fazhan, Wang, Ya, Du, Jiangfeng

Issue&Volume: 2025-11-26

Abstract: Detecting individual spins—including stable and metastable states—represents a fundamental challenge in quantum sensing, with broad applications across condensed matter physics1,2, quantum chemistry3 and single-molecule magnetic resonance imaging4,5. Although nitrogen–vacancy (NV) centres in diamond have emerged as powerful nanoscale sensors, their performance for single-spin detection remains constrained by substantial environmental noise and restricted sensing volume6,7. Here we propose and demonstrate an entanglement-enhanced sensing protocol that overcomes these limitations through the strategic use of entangled NV pairs. Our approach achieves a 3.4-fold enhancement in sensitivity and a 1.6-fold improvement in spatial resolution relative to single NV centres under ambient conditions. The protocol uses carefully engineered entangled states that amplify target spin signals through quantum interference while suppressing environmental noise. Crucially, we extend these capabilities to resolve metastable single-spin dynamics, directly observing stochastic transitions between different spin states by identifying state-dependent coupling strengths. This dual functionality enables simultaneous detection of static and dynamic spin species for studying complex quantum systems. The achieved performance establishes entanglement-enhanced sensing as a viable pathway towards atomic-scale characterization of quantum materials and interfaces.

DOI: 10.1038/s41586-025-09790-6

Source: https://www.nature.com/articles/s41586-025-09790-6