Kilohertz electron paramagnetic resonance spectroscopy of single nitrogen centers at zero magnetic field

Fei Kong; Pengju Zhao; Pei Yu; Zhuoyang Qin; Zhehua Huang; Zhecheng Wang; Mengqi Wang; Fazhan Shi; Jiangfeng Du

doi:10.1126/sciadv.aaz8244

Kilohertz electron paramagnetic resonance spectroscopy of single nitrogen centers at zero magnetic field

Sci Adv. 2020 May 27;6(22):eaaz8244. doi: 10.1126/sciadv.aaz8244. eCollection 2020 May.

Authors

Fei Kong^{1

2

3}, Pengju Zhao^{1

2

3}, Pei Yu^{1

2

3}, Zhuoyang Qin^{1

2

3}, Zhehua Huang^{1

2

3}, Zhecheng Wang^{1

2

3}, Mengqi Wang^{1

2

3}, Fazhan Shi^{1

2

3}, Jiangfeng Du^{1

2

3}

Affiliations

¹ Hefei National Laboratory for Physical Sciences at the Microscale and Department of Modern Physics, University of Science and Technology of China, Hefei 230026, China.
² CAS Key Laboratory of Microscale Magnetic Resonance, University of Science and Technology of China, Hefei 230026, China.
³ Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China.

Abstract

Electron paramagnetic resonance (EPR) spectroscopy is among the most important analytical tools in physics, chemistry, and biology. The emergence of nitrogen-vacancy (NV) centers in diamond, serving as an atomic-sized magnetometer, has promoted this technique to single-spin level, even under ambient conditions. Despite the enormous progress in spatial resolution, the current megahertz spectral resolution is still insufficient to resolve key heterogeneous molecular information. A major challenge is the short coherence times of the sample electron spins. Here, we address this challenge by using a magnetic noise-insensitive transition between states of different symmetry. We demonstrate a 27-fold narrower spectrum of single substitutional nitrogen (P1) centers in diamond with a linewidth of several kilohertz, and then some weak couplings can be resolved. Those results show both spatial and spectral advances of NV center-based EPR and provide a route toward analytical (EPR) spectroscopy at the single-molecule level.

Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).