[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