From Cooper-pair glass to unconventional superconductivity: a unified approach to cuprates and pnictides

TL;DR

This paper introduces a microscopic model explaining unconventional superconductivity in cuprates and pnictides as emerging from an incoherent Cooper-pair glass state driven by pair interactions, leading to a unified understanding of their spectral features.

Contribution

It presents a novel microscopic model that unifies the understanding of superconductivity in cuprates and pnictides through pair interactions and a quasi-Bose phase transition.

Findings

Quantitative description of quasiparticle spectra in cuprates and pnictides

Reproduction of universal 'peak-dip-hump' signatures

Explanation of pseudogap phase above Tc

Abstract

We report a microscopic model wherein the unconventional superconductivity emerges from an incoherent `Cooper-pair glass' state. Driven by the pair-pair interaction, a new type of quasi-Bose phase transition is at work. The interaction leads to the unconventional coupling of the quasiparticles to excited pair states, or `super-quasiparticles', with a non-retarded energy-dependent gap. The model describes quantitatively the quasiparticle excitation spectra of both cuprates and pnictides, including the universal `peak-dip-hump' signatures, and for the pseudogap phase above $T_c$. The results show that instantaneous pair-pair interactions account for the SC condensation without a collective mode.