Optically detected magnetic resonance of high-density ensemble of NV− centers in diamond

Optically detected magnetic resonance (ODMR) is a way to characterize the ensemble of NV−centers. Recently, a remarkably sharp dip was observed in the ODMR with a high-density ensemble of NV centers. The model (Zhu et al 2014 Nat. Commun. 5 3424) indicated that such a dip was due to the spin-1 properties of the NV− centers. Here, we present many more details of the analysis to show how this model can be applied to investigate the properties of the NV− centers. By using our model, we have reproduced the ODMR with and without applied external magnetic fields. Additionally, we investigate how the ODMR is affected by the typical parameters of the ensemble NV− centers such as strain distributions, inhomogeneous magnetic fields, and homogeneous broadening width. Our model provides a way to characterize the NV− center from the ODMR, which would be crucial to realize diamond-based quantum information processing.