1. Research Center for Crystal Materials CAS Key Laboratory of Functional Materials and Devices for Special Environments Xinjiang Technical Institute of Physics & Chemistry, CAS Xinjiang Key Laboratory of Electronic Information Materials and Devices 40-1 South Beijing Road Urumqi 830011 P.R. China) E-mails
2. School of Physics and Materials Science Changji University Changji 831100 P.R. China
3. Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences Beijing 100049 P.R. China