Controllable quantum interface between itinerant optical photon and microwave photonic memory Chuan-Sheng Yang, Yan-Lei Zhang, Gaung-Can Guo and Xu-Bo Zou Eur. Phys. J. D, 74 1 (2020) 9 Published online: 22 January 2020 DOI: 10.1140/epjd/e2019-100447-8