Competition between electron-phonon attraction and weak Coulomb repulsion.
Competition between electron-phonon attraction and weak Coulomb repulsion.
复制标题
电子声子吸引力与弱库仑斥力之间的竞争。
作者：
Freericks;Jarrell
Holstein-Hubbard 模型在无限维的极限下进行检验。传统民间传说认为，由于赝势效应，电荷密度波（CDW）阶次受库仑斥力的影响比超导阶次更强烈。我们发现，不相称的 CDW 和超导相都通过库仑斥力稳定，但令人惊讶的是，相称的 CDW 转变温度比超导转变温度更稳定。通过对微扰理论的详细分析，这个令人费解的特征得到了解决。
The Holstein-Hubbard model is examined in the limit of infinite dimensions. Conventional folklore states that charge-density-wave (CDW) order is more strongly affected by Coulomb repulsion than superconducting order because of the pseudopotential effect. We find that both incommensurate CDW and superconducting phases are stabilized by the Coulomb repulsion, but, surprisingly, the commensurate CDW transition temperature is more robust than the superconducting transition temperature. This puzzling feature is resolved by a detailed analysis of perturbation theory.