An implementation of a nitrogen-vacancy micro-pillar array in diamond for a quantum imaging application with improved sensitivity

In this letter, we have fabricated a diamond pillar array device from an in-situ grown nitrogen-vacancy (NV) doped diamond epi-layer. The device can achieve a high-sensitive wide-field imaging of magnetic fields thanks to the elaborately patterned circular truncated cones. Through a simple continuous-wave optically detected magnetic resonance scheme as a demo, a 7-fold improvement in fluorescence collection intensity, a higher signal-to-noise ratio, a 2-fold improvement in the contrast, and a 10-fold increment on the sensitivity have been achieved on the device. With these improvements, the device can resolve a line current one order of magnitudes smaller than the un-patterned NV layer on diamond. For the first time, the artificially patterned NV ensembles have been implemented to an actual wide-field imaging scenario, which will promote wider adoption of 2D sensing/imaging using NVs.