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arXiv · 2402.07705

Genuine and faux single G centers in carbon-implanted silicon

Alrik Durand·Yoann Baron·Félix Cache·Tobias Herzig·Mario Khoury·Sébastien Pezzagna·Jan Meijer·Jean-Michel Hartmann·Shay Reboh·Marco Abbarchi·Isabelle Robert-Philip·Jean-Michel Gérard·Vincent Jacques·Guillaume Cassabois·Anaïs Dréau
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Abstract

Among the wide variety of single fluorescent defects investigated in silicon, numerous studies have focused on color centers with a zero-phonon line around $1.28 \mu$m and identified to a common carbon-complex in silicon, namely the G center. However, inconsistent estimates regarding their quantum efficiency cast doubt on the correct identification of these individual emitters. Through a comparative analysis of their single-photon emission properties, we demonstrate that these single color centers are split in two distinct families of point defects. A first family consists of the genuine single G centers with a well-identified microscopic structure and whose photoluminescence has been investigated on ensemble measurements since the 60's. The remaining defects belong to a new color center, which we will refer to as G$^{\star}$ center, whose atomic configuration has yet to be determined. These results provide a safeguard against future defect misidentifications, which is crucial for further development of quantum technologies relying on G or G$^{\star}$ center quantum properties.

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Alrik Durand, Yoann Baron, Félix Cache, Tobias Herzig, Mario Khoury, Sébastien Pezzagna, Jan Meijer, Jean-Michel Hartmann, Shay Reboh, Marco Abbarchi, Isabelle Robert-Philip, Jean-Michel Gérard, Vincent Jacques, Guillaume Cassabois, Anaïs Dréau. 2024-02-12. Genuine and faux single G centers in carbon-implanted silicon. https://doi.org/10.1103/physrevb.110.l020102

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