铜氧化物超导体中的缺陷、不均匀性和晶格失配的研究

Study on Defects, Inhomogeneity and Lattice Mismatch in High-T_C Oxide Superconductors

讨论了高温超导体中普遍存在的缺陷、不均匀性、晶格失配及其应力钉扎等问题。由于氧化物超导体临界温度与无严重畸变且有足够载流子浓度的CuO2 面有密切关联 ,通过考察载流子浓度和相邻CuO2 层数目对超导电性的影响 ,提出“活性CuO2 面”模型 ,并在此基础上讨论了增加氧化物超导体的“活性CuO2 面”的数目 ,对进一步提高TC 的重要意义。在活性CuO2 面模型的基础上 ,探讨在近邻阳离子层中引入缺陷对实现更高TC 的可能性。

The ubiquitous defect inhomogeneity, lattice mismatch and stress field pinning in high T C superconductors are discussed. In particular, the superconducting critical temperature is associated with CuO 2 layers in which there are enough carrier concentration and no strong distortion. By investigating the effect of number of CuO 2 layer on superconductivity, a model of “alive CuO 2 layer” is discussed. The increase of alive CuO 2 layer is significant for enhancement of T C. On the basis of the model of alive CuO 2 layer, the possibility of T C improvement is investigated by using introducing defects in neighboring cation layers.