Pseudogap Formation and Quantum Phase Transition in Strongly-Correlated Electron Systems

TL;DR

This paper investigates the origin of pseudogap formation in strongly-correlated superconductors, proposing it results from a massive gauge interaction linked to antiferromagnetic fluctuations, and predicts a quantum phase transition at critical doping.

Contribution

It introduces a gauge interaction model explaining pseudogap formation and predicts a quantum phase transition in cuprates based on experimental data.

Findings

Pseudogap arises from a massive gauge interaction between electrons.

A quantum phase transition of the 2D XY universality class is predicted at critical doping.

The gauge boson mass is related to antiferromagnetic fluctuations.

Abstract

Pseudogap formation is an ubiquitous phenomena in strongly-correlated superconductors, for example cuprates, heavy-fermion superconductors, and iron pnictides. As the system is cooled, an energy gap opens in the excitation spectrum before entering the superconducting phase. The origin of formation and the relevancy to the superconductivity remains unclear, which is the most challenging problem in condensed matter physics. Here, using the cuprate as a model, we demonstrate that the formation of pseudogap is due to a massive gauge interaction between electrons, where the mass of the gauge boson, determining the interaction length scale, is the consequence of the remnant antiferromagnetic fluctuation inherited from the parent compounds. Extracting from experimental data, we predict that there is a quantum phase transition belonging to the 2D XY universality class at the critical doping where pseudogap transition vanishes.