Fermi liquid identities for the Infinite U Anderson Model

TL;DR

This paper applies electron gas methods to the infinite U Anderson model using a Schwinger boson approach, deriving key Fermi liquid identities and exploring low-energy excitations within a 1/N expansion.

Contribution

It extends Fermi liquid identities to the infinite U Anderson model with a novel Schwinger boson treatment and discusses implications for lattice extensions and quantum criticality.

Findings

Derivation of Friedel, Yamada-Yosida-Yoshimori, and Shiba-Korringa relations

Identification of Landau amplitudes depending on virtual spinon and holon exchange

Discussion on potential quantum critical point in lattice extension

Abstract

We show how the electron gas methods of Luttinger, Ward and Nozi\`eres can be applied to the infinite U Anderson impurity model within a Schwinger boson treatment. Working to all orders in a 1/N expansion, we show how the Friedel Langreth relationship, the Yamada-Yosida-Yoshimori and the Shiba-Korringa relations can be derived, under the assumption that the spinon and holon fields are gapped. One of the remarkable features of this treatment, is that the Landau amplitudes depend on the exchange of low energy virtual spinons and holons. We end the paper with a discussion on the extension of our approach to the lattice, where the spinon-holon is expected to close at a quantum critical point.