An intrinsic peak-dip-hump and strong coupling effects in $Bi_{2}Sr_{2}CaCu_{2}O_{8+\delta}$ ARPES data near $(\pi,0)$

TL;DR

This paper reveals that the well-known peak-dip-hump structure in Bi2212 ARPES spectra near (π,0) is mainly due to bilayer splitting, but a weaker, distinct PDH structure suggests strong coupling to a magnetic resonance mode.

Contribution

The study distinguishes the traditional peak-dip-hump from a separate PDH feature, linking the latter to magnetic resonance coupling in Bi2212.

Findings

Peak-dip-hump largely due to bilayer splitting

Detection of a weaker, distinct PDH structure

Evidence of strong coupling to magnetic resonance mode

Abstract

A well-known peak-dip-hump structure exists near $(\pi, 0)$ in superconducting state ARPES spectra of $Bi_{2}Sr_{2}CaCu_{2}O_{8+\delta}$ (Bi2212). Here we report results on optimal and overdoped Bi2212 samples indicating the traditional peak-dip-hump structure observed near $(\pi,0)$ is largely due to bilayer splitting. However a separate, much weaker peak-dip hump (PDH) structure distinct from bilayer splitting can be detected near $(\pi, 0)$. This new PDH structure is consistent with electronic coupling to the magnetic resonance mode in Bi2212. Both the dispersion and line shape signatures indicate strong coupling to this mode.