1. Hefei
National Lab for Physical Sciences at Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China
2. Department
of Chemical Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
3. College
of Physics and Electronic Engineering, Nanyang Normal University, Nanyang 473061, P. R. China
4. Key
Lab of Materials for Energy Conversion, Department of Materials Science
and Engineering, University of Science and Technology of China, Hefei, Anhui 230026, China
5. Synergetic Innovation Center of Quantum Information & Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China