Bi-Sr—Ca—Cu—O超导体能带结构的研究

ENERGY BAND STRUCTURE OF Bi-Sr-Ca-Cu-O SUPERCONDUCTORS

利用EHT近似下的紧束缚能带结构计算方法计算了Bi-Sr-Ca-Cu-O超导体的能带结构.计算结果表明费米面在a~*b~*面上是封闭的,费米能级上电子态密度的增加和体系转变温度T_c的提高是相一致的,Cu-O面上Cu和O的净电荷有规律的变化说明Cu-O面上Cu和O的离子价态可影响到该体系的超导电性.

The energy band structures of Bi-Sr-Ca-Ou-o superconductors were calculated by performing the tight-binding calculation method on the basis of EHT approximation. Results show that the Fermi surfaces are closed on the a*b* planes. The increase of electronic state densities on the Fermi level is consistent with the rise of Tc in this system. The regular changes of the net charges of Cu and O indicate that the ionio States of Cu and O in the Cu-O plane may influence the superconductivity of this system.