Linewidth of NV-detected Electron Spin Resonance

A nitrogen-vacancy (NV) center in diamond possesses unique electronic, magnetic and quantum properties enabling magnetic field sensing through optically detected magnetic resonance (ODMR). Due to the extreme sensitivity of an NV center to magnetic fields, the NV is a promising candidate for applications of electron spin resonance (ESR) with single spin sensitivity. In addition to the sensitivity, ESR using a single NV has a significant advantage in spatial resolution of the detection volume over conventional ESR because of the nanometer sensing distance on single NV-detected ESR. In this presentation, we discuss the linewidth of NV-detected ESR. In the experiment, we study NV-detected ESR on substitutional nitrogen centers in diamond and identify components partially contributing to the linewidth. We also discuss differences of the ESR linewidth between conventional and NV-based detection.