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arXiv · 2507.23258

Deterministic and Scalable Coupling of Single 4H-SiC Spin Defects into Bullseye Cavities

Tongyuan Bao·Qi Luo·Ailun Yi·Yingjie Li·Haibo Hu·Xin Ou·Yu Zhou·Qinghai Song
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Abstract

Silicon carbide (SiC) has attracted significant attention as a promising quantum material due to its ability to host long-lived, optically addressable color centers with solid-state photonic interfaces. The CMOS compatibility of 4H-SiCOI (silicon-carbide-on-insulator) makes it an ideal platform for integrated quantum photonic devices and circuits. However, the deterministic integration of single spin defects into high-performance photonic cavities on this platform has remained a key challenge. In this work, we demonstrate the deterministic and scalable coupling of both ensemble (PL4) and single PL6 spin defects into monolithic bullseye cavities on the 4H-SiCOI platform. By tuning the cavity resonance, we achieve a 40-fold enhancement of the zero-phonon line (ZPL) intensity from ensemble PL4 defects, corresponding to a Purcell factor of approximately 5.0. For deterministically coupled single PL6 defects, we observe a threefold increase in the saturated photon count rate, confirm single-photon emission, and demonstrate coherent control of the spin state through optically detected magnetic resonance (ODMR), resonant excitation, and Rabi oscillations. These advancements establish a viable pathway for developing scalable, high-performance SiC-based quantum photonic circuits.

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Tongyuan Bao, Qi Luo, Ailun Yi, Yingjie Li, Haibo Hu, Xin Ou, Yu Zhou, Qinghai Song. 2025-07-31. Deterministic and Scalable Coupling of Single 4H-SiC Spin Defects into Bullseye Cavities. https://arxiv.org/abs/2507.23258

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