Hybrid quantum systems aim at combining the advantages of different physical systems and producing innovative quantum devices. In particular, the hybrid combination of superconducting circuits and spins in solid-state crystals is a versatile platform to explore many quantum electrodynamics problems. Recently, the remote coupling of nitrogen-vacancy center spins in diamond via a superconducting bus was demonstrated. However, a rigorous experimental test of the quantum nature of this hybrid system and, in particular, entanglement is still missing. We review the theoretical ideas to generate and detect entanglement and present our own scheme to achieve this.

中文翻译：

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在混合量子系统中见证纠缠的观点

混合量子系统旨在结合不同物理系统的优势，生产创新的量子器件。特别是，固态晶体中超导电路和自旋的混合组合是探索许多量子电动力学问题的通用平台。最近，通过超导总线对金刚石中氮空位中心自旋的远程耦合进行了演示。然而，对该混合系统的量子性质，特别是纠缠的严格实验测试仍然缺失。我们回顾了生成和检测纠缠的理论思想，并提出了我们自己的方案来实现这一目标。