Department of Physics and Center for Quantum Coherence, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China.
Nat Nanotechnol. 2011 Apr;6(4):242-6. doi: 10.1038/nnano.2011.22. Epub 2011 Feb 27.
The detection of single nuclear spins is an important goal in magnetic resonance spectroscopy. Optically detected magnetic resonance can detect single nuclear spins that are strongly coupled to an electron spin, but the detection of distant nuclear spins that are only weakly coupled to the electron spin has not been considered feasible. Here, using the nitrogen-vacancy centre in diamond as a model system, we numerically demonstrate that it is possible to detect two or more distant nuclear spins that are weakly coupled to a centre electron spin if these nuclear spins are strongly bonded to each other in a cluster. This cluster will stand out from other nuclear spins by virtue of characteristic oscillations imprinted onto the electron spin decoherence profile, which become pronounced under dynamical decoupling control. Under many-pulse dynamical decoupling, the centre electron spin coherence can be used to measure nuclear magnetic resonances of single molecules. This atomic-scale magnetometry should improve the performance of magnetic resonance spectroscopy for applications in chemical, biological, medical and materials research, and could also have applications in solid-state quantum computing.
检测单原子核自旋是磁共振波谱学的一个重要目标。光检测磁共振可以检测与电子自旋强耦合的单原子核自旋，但尚未考虑到检测与电子自旋弱耦合的远距离核自旋是否可行。在这里，我们使用金刚石中的氮空位中心作为模型系统，通过数值模拟证明，如果这些核自旋在一个团簇中彼此强烈结合，那么就有可能检测到两个或更多与中心电子自旋弱耦合的远距离核自旋。由于电子自旋退相干谱上印上了特征振荡，该团簇将与其他核自旋区分开来，而这些特征振荡在动态去耦控制下会变得更加明显。在多脉冲动态去耦下，中心电子自旋相干性可用于测量单分子的核磁共振。这种原子尺度的磁计量学应该会提高磁共振波谱学在化学、生物、医学和材料研究中的应用性能，也可能在固态量子计算中有应用。
