1. Institut für Physik, Universität Rostock, Albert-Einstein-Straße 23, 18059 Rostock, Germany.
2. Interdisciplinary Center for Quantum Information, Zhejiang Province Key Laboratory of Quantum Technology and Device, Department of Physics, Zhejiang University, Hangzhou 310027, Zhejiang Province, China.
3. Physics Department, Electrical Engineering Department, and Solid State Institute,Technion–Israel Institute of Technology, Haifa 32000, Israel.