作者机构:[1]The College of Science, Air Force University of Engineering, Xi'an 710051, China, [2]Electronic Materials Research Laboratory, Key Laboratory of Ministry of Education,Xi'an Jiaotong University, Xi'an 710049, China
相关基金:Project supported by the National Natural Science Foundation of China (Grant Nos 50632030, 10474077 and 60871027), the National Basic Research Program of China (Grant No 2009CB613306), and The Innovation Funds of the College of Science, Air Force University of Engineering, China.