1. Hefei Innovation Research Institute, School of Microelectronics, Beihang University, Hefei 230013, P. R. China
2. International Research Centre Magtop, Institute of Physics, Polish Academy of Sciences, Aleja Lotników 32/46, PL-02668 Warsaw, Poland
3. Consiglio Nazionale delle Ricerche CNR-SPIN, UOS Salerno, I-84084 Fisciano, Salerno, Italy
4. Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, P. R. China
5. Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Mumbai 400005, India