We derive the third-order poor man’s scaling equation for a generic Hamiltonian describing a quantum impurity embedded into an itinerant electron gas. We show that the XYZ Coqblin–Schrieffer model introduced by one of us earlier is algebraically renormalizable in the sense that the form of the Hamiltonian is preserved along the scaling trajectory, write down the scaling equations for the model, and analyze the renormalization group flows in the cases of both constant and pseudogap densities of states.

中文翻译：

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穷人的缩放：重新审视 XYZ Coqblin-Schrieffer 模型

我们推导出了描述嵌入流动电子气中的量子杂质的通用哈密顿量的三阶穷人标度方程。我们证明了我们之前一个人介绍的XYZ Coqblin-Schrieffer 模型是代数可重整的，因为哈密顿量的形式沿缩放轨迹保持不变，写下模型的缩放方程，并分析重整化群流入状态的常数和伪间隙密度的情况。