Pairing Glue Activation in Cuprates within the Quantum Critical Regime

TL;DR

This paper explores how quantum criticality in cuprates facilitates high-temperature superconductivity by activating pairing mechanisms through a complex interplay of broken-symmetry states within a critical regime.

Contribution

It introduces a novel perspective on the role of quantum critical regimes in enabling pairing in cuprates, highlighting a hidden quantum phase transition and the restoration of symmetry.

Findings

Identification of a critical regime where broken-symmetry states combine

Proposal of a large-U ansatz to explain pairing activation

Discovery of a hidden quantum phase transition between Fermi-liquid and non-Fermi-liquid states

Abstract

A grand challenge in many-body quantum physics is to explain the apparent connection between quantum criticality and high-temperature superconductivity in the cuprates and similar systems, such as the iron pnictides and chalcogenides. Here we argue that the quantum-critical regime plays an essential role in activating a strong-pairing mechanism: although pairing bosons create a symmetry-breaking instability which suppresses pairing, the combination of these broken-symmetry states within the critical regime can restore this symmetry for the paired quasiparticles. This condition is shown to be met within a large-U ansatz. A hidden quantum phase transition then arises between a Fermi-liquid and a non-Fermi-liquid broken-symmetry striped state, and a critical regime in which the broken-symmetry states are combined.