1. a State Key Laboratory of Electronic Thin Films and Integrated Devices , University of Electronic Science and Technology of China , Chengdu, 610054, P. R. China
2. b Texas Center for Superconductivity and Department of Physics , University of Houston , Houston, Texas, 77204
3. c Department of Physics and Astronomy , University of Texas at San Antonio , San Antonio, Texas, 78249
4. d Department of Materials Science and Engineering , University of Texas at Arlington , Arlington, Texas, 76019
5. e Department of Electrical and Computer Engineering , University of Texas at San Antonio , San Antonio, Texas, 78249
6. f U.S. Army Research Laboratory, WMRD, Deer Creek Loop , Aberdeen Proving Ground, MD, 21005