Transport properties of Bicrystalline YBCO Superconducting thin film Grain boundary weak-links

• Main Authors: M.F.Chen, 陳美芬
• Other Authors: J.Y.Juang﹔K.H.Wu
• Format: Others
• Language: zh-TW
• Published: 1994
• Online Access: http://ndltd.ncl.edu.tw/handle/79231596342159952646

碩士 === 國立交通大學 === 電子物理學系 === 82 === The transport properties of the bicrystalline YBCO superconducting thin film grain boundary weak-links deposited on SrTiO3 bicrystal substrates by laser ablation have been investigated systematically. It is found that by varying both the oxygen content and misorientation angle of the grain boundary weak-links, the transport properties characteristics can be reproducibly manipulated. For instance, the functional power (P) of dependence dependent critical current (Ic∼(1-T/Tc) ^P) is found to vary from(2.06→1.95→1.84) with the misorientation angle changing from (24°→36.8°→45°). Whereas when oxygen content varies from fully oxygenated state (X≒7.0 in YBa2Cu3Ox to oxygen-deficient state (X≒6.9) P changes from P≒1.98 to P≒0.89 correspondently. The results demostrated that it is possible to directly manipulate the weak- link properties . In addition, we also found that by irradiating 12.4GHz microwave to the weak-links significant enhancement of superconductivity was realized. The possible physical mechanisms responsible for all the observed results are discussed.