Fast optoelectronic charge state conversion of silicon vacancies in diamond

• Published in: arXiv.org 2023-10
• Main Authors: Rieger, Manuel, Villafane, Viviana, Todenhagen, Lina M, Matthies, Stephan, Appel, Stefan, Brandt, Martin S, Mueller, Kai, Finley, Jonathan J
• Format: Article
• Language: English
• Subjects: Color centers; Control methods; Conversion; Diamonds; Divacancies; Optical activity; Optical pumping; Optoelectronics; Photoluminescence; Qubits (quantum computing); Silicon
• ISSN: 2331-8422
• DOI: 10.48550/arxiv.2310.12288

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.