Surface Roughness Electric Field Noise and Total Noise Effects on Decoherence Time in NV Center Diamond Applications

Noise is a detrimental issue for nitrogen vacancy (NV) center diamond sensing devices. We study the effects of the varying charge density fluctuations and photon scattering caused by the rough surface on the noise spectrum. We apply the Schottky approximation with trapped charge density statistics to calculate and analyze the varying charge density noise spectrum. For the photon scattering noise spectrum, we apply the Green's function method with a Gaussian rough surface correlation. We find that the charge density noise source is prevalent throughout the entire operation frequency regime. The photon scattering noise is larger for the pump beam when compared to the probe beam often used in experimental setups. We also find that noise spectrum does not change when changing the roughness correlation length. This leads to the experimental setup being very important for reducing noise from photon scattering. With these two noise sources, as well as noise sources derived from electric and magnetic field fluctuations in our previous works, we calculate the change in T2 decoherence time. This relation allowed us to determine the change in decoherence time from each noise source and compare.