arXiv:2508.18991 · Nano Letters

Optical Charge State Manipulation of Lead-Vacancy Centers in Diamond

Yiyang Chen, Yoshiyuki Miyamoto, Eiki Ota, Ryotaro Abe, Takashi Taniguchi, Shinobu Onoda, Mutsuko Hatano, Takayuki Iwasaki

Published Nov 13, 2025• 2 citations

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Abstract

Group-IV vacancy centers in diamond exhibit excellent optical and spin coherence properties, making them highly promising and scalable spin qubit candidates. Since only specific charge states are magneto-optically active, control over the charge state is fundamental for quantum applications. Here, we realize the charge state control of lead-vacancy centers (PbV) through multicolor laser irradiation. We achieve tunable population manipulation of the negatively charged state from 0 to 89%, paving the way for spin control of the negatively charged PbV center. Furthermore, through analysis of charge state dynamics, we propose a charge cycle between the neutral and negatively charged states, indicating a possible pathway to the neutral PbV center with a spin-1 system.

DOI: 10.1021/acs.nanolett.5c04448

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