[1] Henan Normal Univ, Sch Phys, Xinxiang 453007, Henan, Peoples R China
[2] Henan Normal Univ, Henan Key Lab Boron Chem & Adv Energy Mat, Xinxiang 453007, Henan, Peoples R China
[3] Univ Calif Irvine, Dept Phys & Astron, Irvine, CA 92697 USA
[4] Univ Michigan, Dept Mech Engn, Ann Arbor, MI 48109 USA
[5] East China Normal Univ, Key Lab Polar Mat & Devices MOE, Shanghai 200062, Peoples R China
[6] East China Normal Univ, Dept Optoelect, Shanghai 200062, Peoples R China
[7] Suzhou Univ Sci & Technol, Sch Math & Phys, Suzhou 215009, Jiangsu, Peoples R China
[8] Jinan Univ, Dept Phys, Guangdong Prov Engn Technol Res Ctr Vacuum Coatin, Siyuan Lab, Guangzhou 510632, Peoples R China