Entanglement plays a vital role in quantum information processing. Owing to its unique material properties, silicon carbide recently emerged as a promising candidate for the scalable implementation of advanced quantum information processing capabilities. To date, however, only entanglement of nuclear spins has been reported in silicon carbide, while an entangled photon source, whether it is based on bulk or chip-scale technologies, has remained elusive. Here, we report the demonstration of an entangled photon source in an integrated silicon carbide platform for the first time. Specifically, strongly correlated photon pairs are efficiently generated at the telecom C-band wavelength through implementing spontaneous four-wave mixing in a compact microring resonator in the 4H-silicon-carbide-on-insulator platform. The maximum coincidence-to-accidental ratio exceeds 600 at a pump power of 0.17 mW, corresponding to a pair generation rate of (9 ± 1) × 10³ pairs/s. Energy-time entanglement is created and verified for such signal-idler photon pairs, with the two-photon interference fringes exhibiting a visibility larger than 99%. The heralded single-photon properties are also measured, with the heralded g⁽²⁾(0) on the order of 10⁻³, demonstrating the SiC platform as a prospective fully integrated, complementary metal-oxide-semiconductor compatible single-photon source for quantum applications.

纠缠在量子信息处理中起着至关重要的作用。由于其独特的材料特性，碳化硅最近成为可扩展实施先进量子信息处理能力的有希望的候选者。然而，迄今为止，碳化硅中仅报道了核自旋纠缠，而纠缠光子源，无论是基于块体技术还是芯片级技术，仍然难以捉摸。在这里，我们首次报告了集成碳化硅平台中纠缠光子源的演示。具体而言，通过在 4H 绝缘体上碳化硅平台的紧凑型微环谐振器中实现自发四波混频，可以在电信 C 波段波长有效生成强相关光子对。当泵浦功率为0.17 mW时，最大符合与意外比超过600，对应于(9 ± 1) × 10 ³对/s的电对生成速率。针对此类信号闲频光子对创建并验证了能量时间纠缠，双光子干涉条纹的可见度大于 99%。还测量了预示的单光子特性，预示的g ⁽²⁾ (0) 约为 10 ^-3，证明 SiC 平台作为一种前瞻性的完全集成、互补金属氧化物半导体兼容的单光子源量子应用。