Numerical renormalization group calculations for the self-energy of the impurity Anderson model
Numerical renormalization group calculations for the self-energy of the impurity Anderson model
复制标题
DOI：
10.1088/0953-8984/10/37/021
复制
发表时间：
1998-09-21
影响因子：
2.7
通讯作者：
Pruschke, T
中科院分区：
文献类型：
--
作者：
Bulla, R;Hewson, AC;Pruschke, T
本文提出了一种用Wilson数值重整化群方法直接计算杂质安德森模型单粒子自能的新方法。结果表明，这种计算Sigma（z）的方法比仅通过杂质绿色函数的方法可靠得多，也更准确。我们给出的自能的情况下，杂质和导带之间的常数耦合（Im Delta（ω + i 0（+））=常数）和有效的Delta（z）中产生的动力学平均场理论的Hubbard模型。本文还讨论了Hubbard模型中金属-绝缘体相变问题的意义。
We present a new method for calculating directly the one-particle self-energy of an impurity Anderson model with Wilson's numerical renormalization group method by writing this quantity as the ratio of two correlation functions. This way of calculating Sigma(z) turns out to be considerably more reliable and accurate than that via the impurity Green's function alone. We give results for the self-energy for the case of a constant coupling between the impurity and the conduction band (Im Delta(omega + i0(+)) = constant) and the effective Delta(z) arising in the dynamical mean-field theory of the Hubbard model. The implications of the problem of the metal-insulator transition in the Hubbard model are also discussed.