论文标题
Eliashberg Jahn-Teller-Hubbard模型的理论
Eliashberg theory of the Jahn-Teller-Hubbard model
论文作者
论文摘要
我们研究了与局部Jahn-Teller Phonons结合的多型哈伯德模型，以研究在富勒里德体中实现的超导状态。一种弱耦合方法与局部自我能源近似结合使用。除了电子的正常和异常的自我能量外，我们还考虑了声子自我能源，这允许对能量学的自洽处理。使用数值计算，详细研究了自我能力及其特征系数的频率依赖性及其特征系数（例如重新规定因素和阻尼）。澄清说，各向异性声子在超导状态的稳定中起着重要作用。通过将完整的结果与没有声子自我能力的结果进行比较，我们表明，超导性通过声子频率的软化稳定。还考虑了电子波动的效果，这导致与轨道的耦合，这是电子气体中等离子体的类似物。这种额外的贡献进一步稳定了超导状态。
We study a multiorbital Hubbard model coupled to local Jahn-Teller phonons to investigate the superconducting state realized in fullerides. A weak-coupling approach is employed in combination with a local self-energy approximation. In addition to the normal and anomalous self-energies of the electrons, we consider the phonon self-energy, which allows a self-consistent treatment of the energetics. The frequency dependence of the self-energies and their characteristic coefficients, such as renormalization factors and dampings, are investigated in detail using numerical calculations. It is clarified that the anisotropic phonons play an important role in the stabilization of the superconducting state. By comparing the full results to those without phonon self-energies, we show that the superconductivity is stabilized by the softening of the phonon frequency. The effects of electronic fluctuations are also considered, which leads to the coupling to orbitons, an analog of plasmons in the electron gas. This additional contribution further stabilizes the superconducting state.
