* Corresponding authors

^a School of Electronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu 610054, P. R. China
E-mail: lxs@uestc.edu.cn, yfchen@uestc.edu.cn
Tel: +86-28-83201970

^b State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054, P. R. China

^c Mechanical Engineering Department, Sichuan University – Pittsburgh Institute, Sichuan University, Jiang'an Campus, Chengdu 610207, P. R. China
E-mail: richardstehle@scupi.cn