Bichromatic microwave manipulation of the NV center nuclear spin using transition not detectable via optically detected magnetic resonance

Recently, rotation sensors utilizing the nuclear spins of nitrogen-vacancy color centers in diamond have been demonstrated. However, these devices are power intensive and challenging to integrate into small chip-based radiofrequency antennas and circuits necessary for controlling nuclear spins or producing relatively high magnetic fields. To address this issue, the coherent manipulation of nuclear spins via coherent population trapping at moderate magnetic fields using microwave fields has been successfully demonstrated in isotopically pure diamond. In this work, we demonstrate that a similar technique can be applied to a diamond plate with a natural abundance of carbon-13, which holds significant potential for practical sensing applications. Although the forbidden resonances required for coherent control were only partially observed, coherent population trapping was successfully demonstrated at both visible and invisible transitions, with an apparent contrast of up to 98 \ifmmode\pm\else\textpm\fi{} 11% and a true contrast of approximately 35 \ifmmode\pm\else\textpm\fi{} 7%. This finding confirms the feasibility of coherent nuclear spin control even in diamond plates with naturally occurring carbon-13.