摘要
本文提出了平均电离势<U_0>的概念,并对氧化物超导体的平均电离势进行了研究.结果表明,具有超导电性的氧化物其<U_0>值比较集中,在10.20～10.50eV的范围内,而非超导氧化物的<U_0>值比较分散.这可做为氧化物超导电性的一个标志或判据.在Y(123)中,氧含量的变化导致T_c随<U_0>的增加而增加,但阳离子的变化则导致T_c随<U_0>的增加而减小.不过两者都是通过改变体系<U_0>值而引起T_c变化的.<U_0>与超导电性存在着密切的联系.
The concept of mean ionization potential of crystal <U0> is proposed, and the <U0> of Oxide Superconduetors is investigated in this paper. The result shows, that the <U0> values of almost all supercondueting oxides cencentrate in a narrow rarge from 10.20 to 10.50eV, while that of non-superconducting oxides scatter outside this region. This characteristics may be then as a new mark or criterion for oxide superconductivity. In Y(123), the variation of oxygen content results in the increase of Tc upon increase of < U0>, while the substitution of Ba2+ by Sr2+ results in the increase of Tc upon increase of < U0>. However in both cases, the variation of Tc is caused by the change of < U0 >. So the mean ionization potential < U0 > is closely correlated with the superconductivity of oxides.
基金
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