Monitoring Dark-State Dynamics of a Single Nitrogen-Vacancy Center in Nanodiamond by Auto-Correlation Spectroscopy: Photonionization and Recharging

Abstract

In this letter, the photon-induced charge conversion dynamics of a single Nitrogen-Vacancy (NV) center in nanodiamond between two charge states, negative (NV−) and neutral (NV0), is studied by the auto-correlation function. It is observed that the ionization of NV− converts to NV0, which is regarded as the dark state of the NV−, leading to fluorescence intermittency in single NV centers. A new method, based on the auto-correlation calculation of the time-course fluorescence intensity from NV centers, was developed to quantify the transition kinetics and yielded the calculation of transition rates from NV− to NV0 (ionization) and from NV0 to NV− (recharging). Based on our experimental investigation, we found that the NV−-NV0 transition is wavelength-dependent, and more frequent transitions were observed when short-wavelength illumination was used. From the analysis of the auto-correlation curve, it is found that the transition time of NV− to NV0 (ionization) is around 0.1 μs, but the transition time of NV0 to NV− (recharging) is around 20 ms. Power-dependent measurements reveal that the ionization rate increases linearly with the laser power, while the recharging rate has a quadratic increase with the laser power. This difference suggests that the ionization in the NV center is a one-photon process, while the recharging of NV0 to NV− is a two-photon process. This work, which offers theoretical and experimental explanations of the emission property of a single NV center, is expected to help the utilization of the NV center for quantum information science, quantum communication, and quantum bioimaging.

Advances in nano- and microscale NMR spectroscopy using diamond quantum sensors

“…While single NV centers have superior spatial resolution, there are certain drawbacks including tedious co-localization of the sample and a suitable NV center, 13,16,80 intrinsically inhomogeneous properties 36,41,80 and instability of single, near-surface NV centers. 81,82 Furthermore, the detection of single photons make these experiments susceptible to background fluorescence. Consequently, the overall experimental complexity of single NV center experiments 83 with long averaging times and background fluorescence results in a low throughput for troubleshooting and/or detection of large parameter spaces.…”

Advances in nano- and microscale NMR spectroscopy using diamond quantum sensors

“…While single NV centers have a superior spatial resolution, there are certain drawbacks including tedious co-localization of the sample and a suitable NV center 13,16,80 , intrinsically inhomogeneous properties 36,41,80 and instability of single, near-surface NV centers 81,82 . Furthermore, the detection of single photons make these experiments susceptible to background fluorescence.…”