Three energy scales in the superconducting state of hole-doped cuprates detected by electronic Raman scattering

TL;DR

This study uses electronic Raman scattering to identify three distinct energy scales in the superconducting state of hole-doped cuprates, revealing doping-dependent behaviors linked to Fermi surface topology and competing orders.

Contribution

It uncovers three universal energy scales in hole-doped cuprates and links their doping dependence to Fermi surface changes and competing orders.

Findings

Three energy scales in A1g, B1g, B2g symmetries vary with doping.

Energy scales merge above p=0.22 and become undetectable below p=0.12.

Doping dependence suggests Fermi surface topology influences superconducting properties.

Abstract

We explored by electronic Raman scattering the superconducting state of Bi-2212 single crystal by performing a fine tuned doping study. We found three distinct energy scales in A1g, B1g and B2g symmetries which show three distinct doping dependencies. Above p=0.22 the three energies merge, below p=0.12, the A1g scale is no more detectable while the B1g and B2g scales become constant in energy. In between, the A1g and B1g scales increase monotonically with under-doping while the B2g one exhibits a maximum at p=0.16. The three superconducting energy scales appear to be an universal feature of hole-doped cuprates. We propose that the non trivial doping dependence of the three scales originates from Fermi surface topology changes and reveals competing orders inside the superconducting dome.