【摘要】 在几个恒定磁场中，测量了不同磁场取向下ＹＢａ２Ｃｕ３Ｏ７外延薄膜的电阻转变曲线。实验结果表明，由不同约化电阻判据确定的特征温度Ｔ＊、有效钉扎势Ｕ以及临界电流密度Ｊｃ均随着磁场与膜面的夹角增大而变化，并表现出相同的变化规律。在夹角小于７５范围内，本征钉扎机制起支配作用；而在９０附近，沿ｃ轴方向的二维缺陷等对磁通线的钉扎作用十分明显。更多还原

【Abstract】 The resistive broadening and the critical current density,of an epitaxial YBa2Cu3O7- thin film atseveral fixed magnetic fields have been measured as a function of the angle between applied magneticfield and the film. The results show that the angular dependence of the characteristic temperatureT* determined by different reduced resistivity criteria, the effective pinning potential and the criticalcurrent density follow the prediction of the intrinsic pinning model for the angle changing from 0 to 75 , illustrating the strong planar pinning mechanism. The anomalous peaks of the characteristictemperature T*, the effective pinning potential and the critical current density were observed near 90 ,which indicate that 2D defects along c-axis are responsible for the effect of flux line pinning.更多还原