1. Dip. di Fisica “E. Pancini,”, Università degli Studi di Napoli Federico II, Napoli, Italy
2. Photon Technology (Zhejiang) Company, Ltd., Jiashan, China
3. Politecnico di Milano, Department of Electronics and Information, Milano, Italy
4. CNR-SPIN Institute of Superconductors, Innovative Materials and Devices, Pozzuoli, Italy
5. Shanghai Key Laboratory of Supercoductor Integrated Circuit Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai, China