[1] Chinese Acad Sci, Inst Phys, Beijing Natl Lab Condensed Matter Phys, Renewable Energy Lab, Beijing 100190, Peoples R China
[2] Chinese Acad Sci, Inst Phys, Huairou Div, Beijing 101407, Peoples R China
[3] Univ Chinese Acad Sci, Coll Mat Sci & Optoelect Technol, Beijing 100049, Peoples R China
[4] Univ Chinese Acad Sci, Sch Phys Sci, Beijing 100049, Peoples R China
[5] Songshan Lake Mat Lab, Dongguan 523808, Guangdong, Peoples R China