不同对称性下超导电性的研究

对序参量用单个基函数展开时的超导电性作了系统的计算，结果表明，为了得到相同的T_c，不同对称性所需要的耦合强度是不一样的；各向异性序参量相应的2Δ(0)/k_BT_c和ΔC_es(T_c)/C_en(T_c)值与BCS理论值有很大的不同。要解释高温超导电性的实验结果，只考虑单波展开是不够的，应该进一步研究两个或多个波混合的情况。通过对实验结果的分析和对混合波情况的初步研究，我们认为d_x²-y²+s*混合波对称性能够与较多的实验结果相吻合。

The Research of Superconductivity under Various Symmetries

The systematic calculation of superconductivity for the order parameter expandedby the single basis function has been made. The results show that the coupling strength needed for getting the same value of T_c for various symmetries of the order parameter is not the same. The values of 2Δ(0)/k_BT_c and ΔC_es(T_c)/C_en(T_c) for the anisotropic order parameters are very different from the corresponding values of BCS theory. In order to explain the experimental results of high-T_c superconductivity, it is not sufficient to consider the single wave expansion only. The cases including two or more components should be considered. Moreover, through the analysis of the experimental results and the preliminary study of the mixed waves cases. we think that the d_x²-y2+s* mixed wave symmetry may better fits the relevant experimental results.