Microwave quantum photonics in superconducting circuits

Those successful demonstrations of manipulating and detecting the quantum states of microwave photons indicate that superconducting quantum circuits will also be versatile tools in interfacing quantum information between different quantum systems in the microwave domain. Hybrid systems combining superconducting quantum circuits with spin ensembles as well as nanoelectromechanical systems have demonstrated coherent coupling in between [14-18]. Furthermore, quantum interface between microwave and optical photons based on those hybrid constructions are currently investigated [19-21].