Two Gaps Make a High Temperature Superconductor?

TL;DR

This paper reviews experimental evidence supporting a two-gap scenario in high-temperature cuprate superconductors, where both superconducting gap and pseudogap coexist across the entire superconducting phase, shedding light on the pairing mechanism.

Contribution

It synthesizes extensive experimental data to support the coexistence of two energy gaps, advancing understanding of high-temperature superconductivity mechanisms.

Findings

Evidence for a coexisting two-gap scenario in cuprates.

Superconducting gap and pseudogap coexist across the superconducting dome.

Implications for the pairing mechanism in high-Tc superconductors.

Abstract

One of the keys to the high-temperature superconductivity puzzle is the identification of the energy scales associated with the emergence of a coherent condensate of superconducting electron pairs. These might provide a measure of the pairing strength and of the coherence of the superfluid, and ultimately reveal the nature of the elusive pairing mechanism in the superconducting cuprates. To this end, a great deal of effort has been devoted to investigating the connection between the superconducting transition temperature Tc and the normal-state pseudogap crossover temperature T*. Here we present a review of a large body of experimental data that suggests a coexisting two-gap scenario, i.e. superconducting gap and pseudogap, over the whole superconducting dome.