Energy levels of nitrogen-vacancy centers in diamond were investigated using optically detected magnetic-resonance spectroscopy near the electronic ground-state level anticrossing (GSLAC) at an axial magnetic field around 102.4~mT in diamond samples with a nitrogen concentration of 1~ppm and 200~ppm. By applying radiowaves in the frequency ranges from 0 to 40 MHz and from 5.6 to 5.9 GHz, we observed transitions that involve energy levels mixed by the hyperfine interaction. We developed a theoretical model that describes the level mixing, transition energies, and transition strengths between the ground-state sublevels, including the coupling to the nuclear spin of the NV center\textquotesingle s 14N and 13C atoms. The calculations were combined with the experimental results by fitting the ODMR spectral lines based on a theoretical model, which yielded information about the polarization of nuclear spins. This study is important for the optimization of experimental conditions in GSLAC-based applications, e.g., microwave-free magnetometry and microwave-free nuclear-magnetic-resonance probes.
@article{arxiv.1805.01251,
title = {Hyperfine level structure in nitrogen-vacancy centers near the ground-state level anticrossing},
author = {Marcis Auzinsh and Andris Berzins and Dmitry Budker and Laima Busaite and Ruvin Ferber and Florian Gahbauer and Reinis Lazda and Arne Wickenbrock and Huijie Zheng},
journal= {arXiv preprint arXiv:1805.01251},
year = {2019}
}
Comments
Significant changes from v2: 1) Reinserted treatment of high-density (200ppm) sample; 2) updated paper to version accepted for publication