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arXiv · 2305.15160

Dopant-assisted stabilization of negatively charged single nitrogen-vacancy centers in phosphorus-doped diamond at low temperatures

Jianpei Geng·Tetyana Shalomayeva·Mariia Gryzlova·Amlan Mukherjee·Santo Santonocito·Dzhavid Dzhavadzade·Durga Dasari·Hiromitsu Kato·Rainer Stöhr·Andrej Denisenko·Norikazu Mizuochi·Jörg Wrachtrup
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Abstract

Charge state instabilities have been a bottleneck for the implementation of solid-state spin systems and pose a major challenge to the development of spin-based quantum technologies. Here we investigate the stabilization of negatively charged nitrogen-vacancy (NV$^-$) centers in phosphorus-doped diamond at liquid helium temperatures. Photoionization of phosphorous donors in conjunction with charge diffusion at the nanoscale enhances NV$^0$ to NV$^-$ conversion and stabilizes the NV$^-$ charge state without the need for an additional repump laser. The phosphorus-assisted stabilization is explored and confirmed both with experiments and our theoretical model. Stable photoluminescence-excitation spectra are obtained for NV$^-$ centers created during the growth. The fluorescence is continuously recorded under resonant excitation to real-time monitor the charge state and the ionization and recombination rates are extracted from time traces. We find a linear laser power dependence of the recombination rate as opposed to the conventional quadratic dependence, which is attributed to the photo-ionization of phosphorus atoms.

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Jianpei Geng, Tetyana Shalomayeva, Mariia Gryzlova, Amlan Mukherjee, Santo Santonocito, Dzhavid Dzhavadzade, Durga Dasari, Hiromitsu Kato, Rainer Stöhr, Andrej Denisenko, Norikazu Mizuochi, Jörg Wrachtrup. 2023-05-24. Dopant-assisted stabilization of negatively charged single nitrogen-vacancy centers in phosphorus-doped diamond at low temperatures. https://doi.org/10.1038/s41534-023-00777-7

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