论文标题
强烈电子排斥的有吸引力的效果 - 顶点差异的物理
Attractive effect of a strong electronic repulsion -- the physics of vertex divergences
论文作者
论文摘要
尽管多电子问题的扰动扩展的崩溃有几种形式的后果，但在这里我们揭示其物理效果：在特定散射通道中倾斜有效电子相互作用的迹象。通过通过其频谱表示分解哈伯德模型的局部和统一的敏感性，我们证明了进入非扰动制度的方式如何增加电荷响应的增强，最终导致接近MOTT MIT的相位分离不稳定性。我们的分析开辟了一条新的途径，以理解非扰动制度中的相位转变，并阐明了为什么从强烈的排斥力中产生的有吸引力的效果会引起相位分离，而不是S波配对或电荷密度波不稳定性。
While the breakdown of the perturbation expansion for the many-electron problem has several formal consequences, here we unveil its physical effect: Flipping the sign of the effective electronic interaction in specific scattering channels. By decomposing local and uniform susceptibilities of the Hubbard model via their spectral representations, we prove how entering the non-perturbative regime causes an enhancement of the charge response, ultimately responsible for the phase-separation instabilities close to the Mott MIT. Our analysis opens a new route for understanding phase-transitions in the non-perturbative regime and clarifies why attractive effects emerging from a strong repulsion can induce phase-separations, but not s-wave pairing or charge-density wave instabilities.
