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arXiv · 2605.26071

Theory of Electrically Detected Magnetic Resonance of Silicon Vacancy-Related Spin Pairs in Silicon Carbide

David A. Fehr·Corey J. Cochrane·Stephen R. McMillan·Nicholas J. Harmon·Patrick M. Lenahan·Michael E. Flatté
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Abstract

We present a quantitative theory for simulating the electrically detected magnetic resonance (EDMR) of silicon vacancy-related spin pairs in silicon carbide using steady-state Lindblad master equations. In our theory, we consider V1a and V2a deep level silicon vacancies near the (0/-) charge state transition level in proximity to a previously identified nitrogen-related complex, the incomplete K-center, due to the hyperfine, spin structure, and Landé g factor of the shallow state. Our theory describes recent room temperature measurements attributed to V1a silicon vacancies, with reasonable extracted parameters for defect spin coherence times and electrical transport rates. At lower temperatures we predict that the shallow level hyperfine structure may be spectrally resolvable. Finally, we predict the EDMR spectrum of V2a silicon vacancy-related spin pairs and predict that two-photon, double quantum transitions of the silicon vacancy's negative charge state can be electrically read-out for enhanced magnetic field sensing.

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David A. Fehr, Corey J. Cochrane, Stephen R. McMillan, Nicholas J. Harmon, Patrick M. Lenahan, Michael E. Flatté. 2026-05-25. Theory of Electrically Detected Magnetic Resonance of Silicon Vacancy-Related Spin Pairs in Silicon Carbide. https://arxiv.org/abs/2605.26071

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