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arXiv · 2605.07891

Phonon-assisted charge-cycling of nitrogen-vacancy centres in diamond

M. Olney-Fraser·J. Fuhrmann·S. Dietel·L. Kazak·F. Jelezko
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Abstract

The nitrogen-vacancy (NV) centre in diamond is a leading platform for room-temperature quantum sensing. Improvements in sensitivity require precise control of the NV charge state. Transitions from the neutral NV$^0$ charge state to the negative NV$^-$ charge state can occur during excitation with photon energies below the ZPL transition of NV$^0$. These sub-resonant charge transitions limit modern initialisation protocols and have not been studied in full detail. In this paper we show that sub-resonant charge cycling arises from phonon-assisted anti-Stokes excitation. We further uncover the phonon states which contribute most strongly to the anti-Stokes transition via the development of novel quantitative models. The models indicate that low energy acoustic phonons strongly contribute to the transition close to the ZPL. At longer wavelengths a 43\,meV mode additionally impacts the charge cycling dynamics.

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M. Olney-Fraser, J. Fuhrmann, S. Dietel, L. Kazak, F. Jelezko. 2026-05-08. Phonon-assisted charge-cycling of nitrogen-vacancy centres in diamond. https://arxiv.org/abs/2605.07891

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