Lo Wing Ki, Zhang Yaowen, Chow Ho Yin, Wu Jiahao, Leung Man Yin, Ho Kin On, Du Xuliang, Chen Yifan, Shen Yang, Pan Ding, Yang Sen
Department of Physics, The Hong Kong University of Science and Technology, Hong Kong, China.
Department of Chemistry, The Hong Kong University of Science and Technology, Hong Kong, China.
Nat Commun. 2025 Jul 1;16(1):5984. doi: 10.1038/s41467-025-61026-3.
Shallow nitrogen-vacancy (NV) centers in diamond are promising quantum sensors but suffer from noise-induced short coherence times due to bulk and surface impurities. We present interfacial engineering via oxygen termination and graphene patching, extending shallow NV coherence to over 1 ms, approaching the T limit. Raman spectroscopy and density-functional theory reveal surface termination-driven graphene charge transfer reduces spin noise by pairing surface electrons, supported by double electron-electron resonance spectroscopy showing fewer unpaired spins. Enhanced sensitivity enables detection of single weakly coupled C nuclear spins and external B spins from a hexagonal boron nitride (h-BN) layer, achieving nanoscale nuclear magnetic resonance. A protective h-BN top layer stabilizes the platform, ensuring robustness against harsh treatments and compatibility with target materials. This integrated approach advances practical quantum sensing by combining extended coherence, improved sensitivity, and device durability.
金刚石中的浅氮空位（NV）中心是很有前途的量子传感器，但由于体相和表面杂质，会受到噪声诱导的短相干时间的影响。我们通过氧终止和石墨烯修补进行界面工程，将浅NV相干时间延长至1毫秒以上，接近T极限。拉曼光谱和密度泛函理论表明，表面终止驱动的石墨烯电荷转移通过配对表面电子来降低自旋噪声，双电子-电子共振光谱也证实未配对自旋减少。增强的灵敏度能够检测来自六方氮化硼（h-BN）层的单个弱耦合C核自旋和外部B自旋，实现纳米级核磁共振。保护性的h-BN顶层稳定了该平台，确保其对苛刻处理具有鲁棒性，并与目标材料兼容。这种集成方法通过结合延长的相干时间、提高的灵敏度和器件耐久性，推动了实用量子传感的发展。
