High-NV-Density Diamonds for Quantum Sensing

Nitrogen-vacancy (NV) centers in diamond are a prominent platform for developing quantum sensing devices. However, the lack of scalable and reproducible methods for producing high quality NV diamond material has hindered the advancement towards the large scale expansion of NV based sensing devices. We examine diamonds fabricated via a chemical vapor deposition process that have reproducible, favorable properties, including dense NV concentrations ($\approx $ 3ppm) and minimal parasitic defects. We measure the volume normalized sensitivity to DC and AC magnetic fields in these samples where both nitrogen-NV and NV-NV interactions limit spin dephasing and decoherence times. Finally, we explore advanced readout techniques to further improve the ultimate sensitivity of this diamond material.