Jarmola, AndreyFescenko, I.Acosta, Victor MDoherty, MarcusFatemi, F. K.Ivanov, T.BUDKER, DMITRYMalinovsky, V. S.2023-06-282023-06-282643-1564http://hdl.handle.net/1885/293763Nuclear spin ensembles in diamond are promising candidates for quantum sensing applications, including rotation sensing. Here we characterize the optically detected nuclear spin transitions associated with the N-14 nuclear spin within diamond nitrogen-vacancy (NV) centers. We observe that the contrast of the nuclearspin-dependent fluorescence is comparable to the contrast of the NV electron-spin-dependent fluorescence. Using Ramsey spectroscopy, we investigate the temperature and magnetic field dependence of the nuclear spin transitions in the 77.5-420 K and 350-675 G range, respectively. The nuclear quadrupole coupling constant Q was found to vary with temperature T, yielding d vertical bar Q vertical bar/dT =-35.0(2) Hz/K at T = 297 K. The temperature and magnetic field dependencies reported here are important for quantum sensing applications such as rotation sensing and potentially for applications in quantum information processing.application/pdfen-AU© 2020 American Physical Societyhttps://creativecommons.org/licenses/by/4.0/202010.1103/PhysRevResearch.2.0230942022-04-10Creative Commons Attribution 4.0 International License