Pseudogap due to antiferromagnetic fluctuations and the phase diagram of the high temperature oxide superconductors

TL;DR

This paper investigates the pseudogap phenomenon in high-temperature oxide superconductors, showing how antiferromagnetic fluctuations influence the density of states and the superconducting transition temperature across different doping levels.

Contribution

It introduces a model linking antiferromagnetic fluctuations to the pseudogap and doping dependence of the transition temperature in high-Tc superconductors.

Findings

Pseudogap reduces the density of states near the Fermi energy.

Superconducting transition temperature decreases with increasing pseudogap.

Pseudogap vanishes at high doping levels.

Abstract

A reduction of the density of states near the Fermi energy in the normal state (pseudogap) of high-temperature oxide superconductors is examined on the basis of the two-dimensional tight-binding model with effective interactions due to antiferromagnetic fluctuations. By using antiferromagnetic correlation lengths which are phenomenologically assumed, the doping dependence of the pseudogap is obtained. The superconducting transition temperature decreases and eventually vanishes due to the pseudogap as the hole concentration is reduced.