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本文从周期性的Anderson晶格模型出发,考虑到局域电子与局域晶格形变的作用,对CeCu2Si2和UBe13的重费密子超导现象进行了理论研究。通过计算,得到了合理的超导转变温度Tc;给出了描述同位素效应大小的参数α<1/2,甚至等于零(在BCS理论中α=1/2),说明现在的理论给出的同位素效应比BCS理论小,甚至可以不存在同位素效应,这与重费密子超导的实验相符合;此外还给出了序参量随温度及态密度变化的关系曲线,由此可The phenomena of the heavy-fermion superconductivity (HFS) of CeCu2Si2 and UBe13 were theoretically inveotigated by starting from the periodic Anderson lattice model and considering the interaction between the localized electrons and the localized lattice deformation. Throngh the calculations, we obtained a reasonable superconducting transition temperature Tc and showed that the parameter which describes the isotopic effect a<1/2, even equals to zero (in BCS theory a = 1/2). We showed that the isotopic effect is smaller in our theory than that in BCS theory, even there could exist no isotopic effect in our model, the result is in agreement with the experimental facts of HFS. In addition, the curves of the order parameters varing with the temperature and the density of state are given and the conclusion of f-electrons to be responsible for HFS can be obtained naturally.
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