Asymptotically exact solution of a local copper-oxide model

TL;DR

This paper provides an asymptotically exact solution to a local copper-oxide model, revealing a phase diagram with a quantum critical point and a marginal-FL spectrum, advancing understanding of strongly correlated electron systems.

Contribution

It introduces an exact solution for a simplified copper-oxide model, elucidating the phase diagram and critical behavior in the strong coupling regime.

Findings

Identifies an exactly solved line crossing the quantum critical point

Reveals a many-particle resonance near the chemical potential

Derives a marginal-FL spectrum for susceptibilities

Abstract

We present an asymptotically exact solution of a local copper-oxide model abstracted from the multi-band models. The phase diagram is obtained through the renormalization-group analysis of the partition function. In the strong coupling regime, we find an exactly solved line, which crosses the quantum critical point of the mixed valence regime separating two different Fermi-liquid (FL) phases. At this critical point, a many-particle resonance is formed near the chemical potential, and a marginal-FL spectrum can be derived for the spin and charge susceptibilities.