Superconductivity in the half-filled Hubbard-Holstein model in the antiadiabatic region

被引：31

作者：

Takada, Y

机构：

[1] Institute for Solid State Physics, University of Tokyo, Minato-ku, Tokyo 106

来源：

JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN | 1996年 / 65卷 / 06期

关键词：

superconductivity; CDW; SDW; isotope effect; narrow band; bipolaron; electron correlation;

D O I：

10.1143/JPSJ.65.1544

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

We study an electron-phonon model with on-site Coulomb repulsions U-ee at half filling by exact diagonalization combined with a mean-field approximation which gives accurate results in the narrow-bandwidth case. Superconductivity with off-site pairing is found to exist with an inverse isotope effect if and only if the phonon-mediated attraction is almost offset by U-ee.

引用

页码：1544 / 1547

页数：4

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