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arXiv · 2412.20039

Tunable cavity coupling to spin defects in 4H-silicon-carbide-on-insulator platform

Tongyuan Bao·Qi Luo·Ailun Yin·Yao Zhang·Haibo Hu·Zhengtong Liu·Shumin Xiao·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. While micro-ring cavities have been extensively studied in SiC and other materials, the integration of 4H-SiC spin defects into these critical structures, along with continuous mode tunability, remains unexplored. In this work, we demonstrate the integration of PL4 divacancy spin defects into tunable micro-ring cavities in scalable thin-film 4H-SiC nanophotonics. Comparing on- and off-resonance conditions, we observed an enhancement of the Purcell factor by approximately 5.0. This enhancement effectively confined coherent photons within the coupled waveguide, leading to a twofold increase in the ODMR (optically detected magnetic resonance) contrast and coherent control of PL4 spins. These advancements lay the foundation for developing SiC-based quantum photonic circuits.

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Tongyuan Bao, Qi Luo, Ailun Yin, Yao Zhang, Haibo Hu, Zhengtong Liu, Shumin Xiao, Xin Ou, Yu Zhou, Qinghai Song. 2024-12-28. Tunable cavity coupling to spin defects in 4H-silicon-carbide-on-insulator platform. https://arxiv.org/abs/2412.20039

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