Weak Pseudogap Behavior in the Underdoped Cuprate Superconductors

TL;DR

This paper presents an exact solution of a spin fermion model showing that high-energy features in underdoped cuprates are driven by strong antiferromagnetic correlations, linking pseudogap behavior to magnetic interactions.

Contribution

It provides a theoretical framework connecting AF correlations with pseudogap phenomena in cuprates, supported by an exact solution and experimental consistency.

Findings

High-energy spectral features are due to AF correlations.

The pseudogap onset temperature relates to AF correlation strength.

Magnetic behavior changes align with NMR observations.

Abstract

We report on an exact solution of the nearly antiferromagnetic Fermi liquid spin fermion model in the limit \pi T << \omega_{sf}, which demonstrates that the broad high energy features found in ARPES measurements of the spectral density of the underdoped cuprate superconductors are determined by strong antiferromagnetic (AF) correlations and precursor effects of an SDW state. We show that the onset temperature, T^{cr}, of weak pseudo-gap (pseudoscaling) behavior is determined by the strength, \xi, of the AF correlations, and obtain the generic changes in low frequency magnetic behavior seen in NMR experiments with \xi(T^{cr}) \approx 2, confirming the Barzykin and Pines crossover criterion.