Theory of antiferromagnetism in the electron-doped cuprate superconductors

TL;DR

This paper develops a theoretical model based on the Hubbard model and fluctuation-exchange approach to explain antiferromagnetism in electron-doped cuprates, aligning well with experimental observations.

Contribution

It introduces a comprehensive theoretical framework incorporating spin fluctuations and impurity effects to describe magnetic properties in electron-doped cuprates.

Findings

Antiferromagnetic transition temperature matches experiments.

Pseudogap onset temperature agrees with observed data.

Density of states shows a zero-energy peak at low doping.

Abstract

On the basis of the Hubbard model, we present the formulation of antiferromagnetism in electron-doped cuprates using the fluctuation-exchange approach. Taking into account the spin fluctuations in combination with the impurity scattering effect due to the randomly distributed dopant-atoms, we investigate the magnetic properties of the system. It is shown that the antiferromagnetic transition temperature, the onset temperature of the pseudogap formation, the single particle spectral density, and the staggered magnetization obtained by the present approach are in very good agreement with the experimental results. The distribution function in momentum space at very low temperature is observed to differ significantly from that of the Fermi liquid. Also, we find zero-energy peak in the density of states (DOS) of the antiferromagnetic phase. This DOS peak is sharp in the low doping regime, and disappears near the optimal doping where the AF order becomes weak.