A competing order scenario of two-gap behavior in hole doped cuprates

TL;DR

This paper proposes a model where the pseudogap in hole-doped cuprates originates from a competing phase, explaining the two-gap phenomena observed in ARPES and STM studies and their doping-dependent behaviors.

Contribution

It introduces a competing order scenario that accounts for the distinct nodal and antinodal gaps and explains experimental observations in ARPES and STM data.

Findings

The pseudogap has a non-superconducting origin in a competing phase.

Superconductivity can suppress the competing order near optimal doping.

Differences between STM and ARPES results provide insights into the symmetry of the competing order.

Abstract

Angle-dependent studies of the gap function provide evidence for the coexistence of two distinct gaps in hole doped cuprates, where the gap near the nodal direction scales with the superconducting transition temperature $T_c$, while that in the antinodal direction scales with the pseudogap temperature. We present model calculations which show that most of the characteristic features observed in the recent angle-resolved photoemission spectroscopy (ARPES) as well as scanning tunneling microscopy (STM) two-gap studies are consistent with a scenario in which the pseudogap has a non-superconducting origin in a competing phase. Our analysis indicates that, near optimal doping, superconductivity can quench the competing order at low temperatures, and that some of the key differences observed between the STM and ARPES results can give insight into the superlattice symmetry of the competing order.