1. College of Optoelectronic Engineering and Key Laboratory of Optoelectronic Technology & Systems Education Ministry of China, Chongqing University, 400044 Chongqing, China
2. The Institute of Materials in Electrical Engineering 1, RWTH Aachen University, 52074 Aachen, Germany
3. School of Electrical Engineering and State Key Laboratory of Power Transmission Equipment & System Security and New Technology, Chongqing University, 400044 Chongqing, China
4. Department of Energy Conversion and Storage, Technical University of Denmark, 2800 Kongens Lyngby, Denmark