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Abstract Nitrogen-vacancy (NV) and silicon-vacancy (SiV) color defects in diamond are promising systems for applications in quantum technology. The NV and SiV centers have multiple charge states, and their charge states have different electronic, optical and spin properties. For the NV centers, most investigations for quantum sensing applications are targeted on the negatively charged NV (NV−), and it is important for the NV centers to be in the NV−state. However, it is known that the NV centers are converted to the neutrally charged state (NV0) under laser excitation. An energetically favorable charge state for the NV and SiV centers depends on their local environments. It is essential to understand and control the charge state dynamics for their quantum applications. In this work, we discuss the charge state dynamics of NV and SiV centers under high-voltage nanosecond pulse discharges. The NV and SiV centers coexist in the diamond crystal. The high-voltage pulses enable manipulating the charge states efficiently. These voltage-induced changes in charge states are probed by their photoluminescence spectral analysis. The analysis result from the present experiment shows that the high-voltage nanosecond pulses cause shifts of the chemical potential and can convert the charge states of NV and SiV centers with the transition rates of ∼MHz. This result also indicates that the major population of the SiV centers in the sample is the doubly negatively charged state (SiV2−), which is often overlooked because of its non-fluorescent and non-magnetic nature. This demonstration paves a path for a method of rapid manipulation of the NV and SiV charge states in the future.
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Probing itinerant carrier dynamics at the diamond surface using single nitrogen vacancy centers
Color centers in diamond are widely explored for applications in quantum sensing, computing, and networking. Their optical, spin, and charge properties have extensively been studied, while their interactions with itinerant carriers are relatively unexplored. Here, we show that NV centers situated 10 ± 5 nm of the diamond surface can be converted to the neutral charge state via hole capture. By measuring the hole capture rate, we extract the capture cross section, which is suppressed by proximity to the diamond surface. The distance dependence is consistent with a carrier diffusion model, indicating that the itinerant carrier lifetime can be long, even at the diamond surface. Measuring dynamics of near-surface NV centers offers a tool for characterizing the diamond surface and investigating charge transport in diamond devices.
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- Award ID(s):
- 1752047
- PAR ID:
- 10425470
- Date Published:
- Journal Name:
- Applied Physics Letters
- Volume:
- 122
- Issue:
- 6
- ISSN:
- 0003-6951
- Page Range / eLocation ID:
- 064002
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1063/5.0130761
