Silicon carbide: A promising platform for scalable quantum networks

Quantum networks based on solid-state spin defects present a transformative approach to secure communication and distributed quantum computing, utilizing quantum entanglement and coherent spin–photon interfaces. Silicon carbide (SiC) stands out as a compelling material platform due to its unique combination of a wide bandgap, high optical nonlinearity, CMOS-compatible fabrication, and controllable spin-active defects. These intrinsic properties facilitate efficient photon emission, robust spin coherence at both room and cryogenic temperatures, and integration with photonic nanostructures. Recent advancements in defect engineering and micro-nanophotonics have unlocked the potential of SiC quantum nodes, which feature electron-nuclear spin systems for high-fidelity quantum operations and long-lived quantum memories. Key steps such as single-shot readout and spin-photon entanglement have been successfully demonstrated, bringing SiC closer to a real quantum network platform. This review offers a comprehensive overview of the advancements in SiC-based quantum networks, encompassing key aspects such as defect fabrication methodologies, optimization of spin-photon interfaces, and strategies for photonic integration. Additionally, it examines the existing challenges and outlines promising future directions in this rapidly evolving field.