Bridging k- and q- Space in the Cuprates: Comparing ARPES and STM Results

TL;DR

This paper compares ARPES and STM measurements in Bi2212, showing they can be reconciled under specific scattering assumptions and clarifying the nature of spectral features, but finds no evidence of bilayer splitting in STM.

Contribution

It provides a detailed comparison between ARPES and STM results in cuprates, clarifying how their data can be consistent and highlighting the nature of spectral features.

Findings

ARPES and STM data can be approximately reconciled with certain scattering assumptions.

The 'peak' in ARPES is a dispersive bright spot, not a bilayer splitting.

No evidence of bilayer splitting is observed in STM data.

Abstract

A critical comparison is made between the ARPES-derived spectral function and STM studies of Friedel-like oscillations in Bi_2Sr_2CaCu_2O_{8+delta} (Bi2212). The data can be made approximately consistent, provided that (a) the elastic scattering seen in ARPES is predominantly small-angle scattering and (b) the `peak' feature seen in ARPES is really a dispersive `bright spot', smeared into a line by limited energy resolution; these are the `bright spots' which control the quasiparticle interferences. However, there is no indication of bilayer splitting in the STM data.