[1] Nanjing Univ Posts & Telecommun, Sch Telecommun & Informat Engn, Nanjing 210023, Peoples R China
[2] Nanjing Univ Posts & Telecommun, Sch Sci, Nanjing 210023, Peoples R China
[3] Nanjing Univ Posts & Telecommun, New Energy Technol Engn Lab Jiangsu Prov, Nanjing 210023, Peoples R China
[4] Zhejiang Univ Sci & Technol, Dept Phys, Hangzhou 310023, Peoples R China
[5] Nanjing Forestry Univ, Co Innovat Ctr Sustainable Forestry Southern Chin, Nanjing 210037, Peoples R China
[6] Nanjing Univ, Natl Lab Solid State Microstruct, Nanjing 210093, Peoples R China