1. Department of Physics, National Cheng Kung University, Tainan 701, Taiwan
2. Institute of Semiconductor Physics, National Academy of Sciences of Ukraine, Kyiv 03028, Ukraine
3. Research Center for Applied Sciences, Academia Sinica, Nankang, Taipei 11529, Taiwan
4. Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan 701, Taiwan
5. Research Center for Energy Technology and Strategy, National Cheng Kung University, Tainan 701, Taiwan