Oxygen-vacancy origin of robust surface-proximity spin centers in silicon carbide

Yu Chen; Qi Zhang; Mingzhe Liu; Junda Wu; Jinpeng Liu; Xin Zhao; Jingyang Zhou; Pei Yu; Shaochun Lin; Yuanhong Teng; Wancheng Yu; Ya Wang; Chang-Kui Duan; Fazhan Shi

doi:10.59717/j.tip.2026.100013

The Innovation Physics > 2026 Vol. 1 > No. 1 > 100013

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Oxygen-vacancy origin of robust surface-proximity spin centers in silicon carbide

1.
Laboratory of Spin Magnetic Resonance, School of Physical Sciences, and Anhui Province Key Laboratory of Scientific Instrument Development and Application, University of Science and Technology of China, Hefei 230026, China
2.
Hefei National Laboratory, University of Science and Technology of China, Hefei 230088, China
3.
School of Biomedical Engineering and Suzhou Institute for Advanced Research, University of Science and Technology of China, Suzhou 215123, China
4.
Institute of Quantum Sensing, Institute of Fundamental and Transdisciplinary Research, Zhejiang Key Laboratory of R&D and Application of Cutting-edge Scientific Instruments, State Key Laboratory of Ocean Sensing, School of Physics, Zhejiang University, Hangzhou 310027, China
5.
State Key Laboratory of Crystal Materials, Institute of Novel Semiconductors, Shandong University, Jinan 250100, China
6.
Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei 230026, China
7.
These authors contributed equally

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Corresponding authors: zhq2011@ustc.edu.cn (Q.Z.); fzshi@ustc.edu.cn (F.S.)
Received Date: May 18, 2026

Accepted Date: September 15, 2026

Published Online: September 20, 2026

The Innovation Physics 1(1), https://doi.org/10.59717/j.tip.2026.100013 | Cite this article

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PUBLIC SUMMARY

PUBLIC SUMMARY
1. PL5 and PL6 in 4H-SiC are key quantum sensors, but their unknown structures block efficient fabrication.
  
  We identify both as oxygen-vacancy complexes and boost their formation yields via oxygen implantation.
  
  This could enable scalable SiC quantum technologies, from sensor arrays to integrated photonic devices.

ABSTRACT

ABSTRACT

Spin defects promise atomic-scale resolution and single-electron sensitivity, but typically deteriorate near surfaces. The PL5 and PL6 centers in SiC have emerged as a notable exception, exhibiting high optical contrast, long spin coherence times, and stable charge states within a few nanometers of the surface at room temperature. However, deterministic creation and scalable fabrication of these centers remain limited by their unresolved microscopic origins, with PL5 and PL6 frequently discussed in connection with divacancies and stacking faults. Here, we show that PL5 and PL6 do not originate from stacking faults, as regions with and without these planar defects exhibit comparable emitter densities. Instead, oxygen implantation increases the yield by more than an order of magnitude compared to nitrogen, and isotopic implantation with ¹⁷O yields a spin-5/2 hyperfine signature in the ODMR spectra, providing direct confirmation of oxygen involvement. From the characterization of the zero-field-splitting tensor and hyperfine interactions, together with ab initio calculations, we assign PL5 and PL6 to O_CV_Si defects in the kh and hh configurations, respectively. These results establish a basis for deterministic generation of near-surface spin qubits and their scalable integration for quantum photonics and nanoscale quantum sensing.
- silicon carbide /
- spin defects /
- oxygen-vacancy complexes /
- quantum sensing /
- quantum photonics

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Chen Y., Zhang Q., Liu M., et al. (2026). Oxygen-vacancy origin of robust surface-proximity spin centers in silicon carbide. The Innovation Physics 1:100013. https://doi.org/10.59717/j.tip.2026.100013

Chen Y., Zhang Q., Liu M., et al. (2026). Oxygen-vacancy origin of robust surface-proximity spin centers in silicon carbide. The Innovation Physics 1:100013. https://doi.org/10.59717/j.tip.2026.100013

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Oxygen-vacancy origin of robust surface-proximity spin centers in silicon carbide

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