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arXiv · 1710.01171

Generalized Schrieffer-Wolff transformation of multi-flavor Hubbard models

Seung-Sup B. Lee·Jan von Delft·Andreas Weichselbaum
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Abstract

We give a self-contained derivation of the low-energy effective interactions of the SU($N$) Hubbard model, a multiflavor generalization of the one-band Hubbard model, by using a generalized Schrieffer-Wolff transformation (SWT). The effective interaction of doublons and holons, which has been largely ignored in previous SWT studies (e.g., the $t$-$J$ model), leads to distinct peaks in the local density of states. As shown by Lee et al. [Phys. Rev. Lett. 119, 236402 (2017)], this underlying effective doublon-holon interaction explains the numerical observation of the subpeaks at the inner edges of the Hubbard bands in the metallic phase close to the Mott transition.

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Seung-Sup B. Lee, Jan von Delft, Andreas Weichselbaum. 2017-12-06. Generalized Schrieffer-Wolff transformation of multi-flavor Hubbard models. https://doi.org/10.1103/physrevb.96.245106

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