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arXiv · 2605.12473

Optical detection of the electron spin resonances of G centers in silicon

Félix Cache·Krithika V. R.·Tobias Herzig·Andrej Yu Kuznetsov·Sébastien Pezzagna·Marco Abbarchi·Isabelle Robert-Philip·Jean-Michel Gérard·Guillaume Cassabois·Vincent Jacques·Anaïs Dréau
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Abstract

Color centers in silicon are emerging as promising platforms for quantum technologies. Among them, the G center has attracted considerable interest owing to its bright telecom O-band single-photon emission and its optically addressable metastable electron-spin triplet state. Here we investigate the spin properties of ensembles of G centers under above-band-gap excitation. We elucidate the spin photo-dynamics giving rise to the optical detected magnetic resonance (ODMR) response of G centers. The optimal pulsed sequence for measuring the ODMR spectrum of the G defects is identified, along with the temperature and optical-power regimes maximizing the spin readout contrast. Through magneto-optical measurements, we detect a level-anticrossing of the G center electron spin states. At last, we demonstrate coherent spin control of the defects, and characterize their spin-coherence properties. Unveiling the spin degree of freedom of the G center opens new avenues for the realization of quantum memories and quantum registers based on silicon color centers.

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Félix Cache, Krithika V. R., Tobias Herzig, Andrej Yu Kuznetsov, Sébastien Pezzagna, Marco Abbarchi, Isabelle Robert-Philip, Jean-Michel Gérard, Guillaume Cassabois, Vincent Jacques, Anaïs Dréau. 2026-05-12. Optical detection of the electron spin resonances of G centers in silicon. https://arxiv.org/abs/2605.12473

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