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arXiv · 2310.12288

Fast optoelectronic charge state conversion of silicon vacancies in diamond

Manuel Rieger·Viviana Villafane·Lina M. Todenhagen·Stephan Matthies·Stefan Appel·Martin S. Brandt·Kai Mueller·Jonathan J. Finley
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Abstract

Group IV vacancy color centers in diamond are promising spin-photon interfaces with strong potential for applications for photonic quantum technologies. Reliable methods for controlling and stabilizing their charge state are urgently needed for scaling to multi-qubit devices. Here, we manipulate the charge state of silicon vacancy (SiV) ensembles by combining luminescence and photo-current spectroscopy. We controllably convert the charge state between the optically active SiV$^-$ and dark SiV$^{2-}$ with MHz rates and 90% contrast by judiciously choosing the local potential applied to in-plane surface electrodes and the laser excitation wavelength. We observe intense SiV$^-$ photoluminescence under hole-capture, measure the intrinsic conversion time from the dark SiV$^{2-}$ to the bright SiV$^-$ to be 36.4(6.7)ms and demonstrate how it can be enhanced by a factor of $10^5$ via optical pumping. Moreover, we obtain new information on the defects that contribute to photo-conductivity, indicating the presence of substitutional nitrogen and divacancies.

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Manuel Rieger, Viviana Villafane, Lina M. Todenhagen, Stephan Matthies, Stefan Appel, Martin S. Brandt, Kai Mueller, Jonathan J. Finley. 2023-10-18. Fast optoelectronic charge state conversion of silicon vacancies in diamond. https://doi.org/10.1126/sciadv.adl4265

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