论文部分内容阅读
报道了ＹＢａ２Ｃｕ３Ｏ７－δ（ＹＢＣＯ）颗粒膜的微波辐射（λ＝８ｍｍ）响应特征．实验结果表明：ＹＢＣＯ颗粒膜的微波响应行为不能用辐射热效应来描述，而应当属于非平衡响应行为．在超导转变温度Ｔｃｏ以下温区，非平衡微波响应信号电平随样品电阻Ｒ趋于零而消失，并且对弱的外磁场十分灵敏．在对样品的直流ＩＶ特性进行了仔细测量后发现，样品的电输运行为具有准二维结构特征，可以用ＫｏｓｔｅｒｌｉｔｚＴｈｏｕｌｅｓ（ＫＴ）相变模型加以描述．在此基础上，分析结果表明：ＹＢＣＯ颗粒膜中的非平衡微波响应机制可能与磁通“涡旋反涡旋”束缚对的激发态有关
The microwave radiation (λ = 8mm) response characteristics of YBa2Cu3O7-δ (YBCO) granular films were reported. The experimental results show that the microwave response behavior of YBCO granular films can not be described by the radiative thermal effect, but should belong to the non-equilibrium response behavior. Under the superconducting transition temperature Tco, the unbalanced microwave response signal level disappears as the sample resistance R tends to zero and is very sensitive to the weak external magnetic field. After careful examination of the DC I-V characteristics of the sample, it was found that the electrical transport behavior of the sample has the quasi-two-dimensional structural characteristics and can be described by the Kosterlitz-Houhou (K-T) phase transition model. On this basis, the analysis results show that the mechanism of unbalanced microwave response in YBCO granular film may be related to the excited state of the “vortex-vortex” binding of the magnetic flux