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本文用数值解方法从Eliashberg方程计算出超导临界温度Tc,并考察Tc对有效声子谱的依赖关系。在这个研究中,a2F(ω)被取为双δ函数谱,并允许其中的谱参数可以在很宽范围内改变。作者发现在λc级数解的收敛圆外),Tc除了依赖λ和矩比外,还依赖Tc级数解的收敛半径倒数Λ;它们之间的关系是有规律的。在这些结果的启示下,本文在μ*=0情形,用弥合数值解的方法得到一个适用于λc近似公式。接着,本文作者对吉光达和吴杭生的一篇文章进行了研究,指出:该文提出的超导体分类建议及其工作的主要结论是对的。但其中对决定A型超导体临界温度主要参量问题进行的分析,只适用于这样一些A型超导体,它们的收敛半径倒数Λ或者比λ0小,或者虽比λ0大、但λ又小于λ0,其中λ0是个依赖谱形状的参量,它的定义在正文中给出。对另一些A型超导体(λ0c的主要参量不再是λ,而是δ=1/∧0.5(ω1/2/ωlog)5.5λ1.55。By using numerical method, the superconducting critical temperature Tc is cal-culated from the Eliashberg equation and the dependence of Tc on λ and the shape of effective phonon spectrum is investigated. In this study, α2F(ω) is taken as the double delta-function spectrum and the spectrum parameters are permited to change over a wide range. It is found with surprising that in the regime of λc series solution, Tc depends, not only on λ and ratios of moments but also on Λ, the reciprocal of the convergence radius of the Tc series solution, and the relation between them shows a certain regularity. Under the light of these results, an approximate Tc formula for the case of μ*= 0 is constructed in the regime of λ 0, or Λ is greater than λ0 but λ is smaller than λ0. Here, λ0 is a parameter depending on the shape of spectrum and its definition is given in this paper. For other type A.superconductors (λ0c is determined is not λ, but δ=1/∧0.5(ω1/2/ωlog)5.5λ1.55.
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