[1] Univ Elect Sci & Technol China, State Key Lab Elect Thin Films & Integrated Devic, Chengdu 610054, Sichuan, Peoples R China
[2] Univ Houston, Dept Phys, Houston, TX 77204 USA
[3] Univ Houston, Texas Ctr Superconduct, Houston, TX 77204 USA
[4] Univ Texas San Antonio, Dept Phys & Astron, San Antonio, TX 78249 USA
[5] Univ Texas San Antonio, Dept Elect & Comp Engn, San Antonio, TX 78249 USA
[6] Los Alamos Natl Lab, Ctr Integrated Nanotechnol, Los Alamos, NM 87545 USA