The joys and pitfalls of Fermi surface mapping in Bi2212 using angle resolved photoemission

TL;DR

This study uses high-resolution angle-resolved photoemission data to clarify the Fermi surface topology in Bi2212, confirming it as hole-like with additional shadow and diffraction features.

Contribution

It provides a definitive, self-consistent mapping of the Bi2212 Fermi surface, resolving previous controversies with dense k-space sampling and high-resolution data.

Findings

Fermi surface is hole-like with rounded tubes at Brillouin zone corners

Shadow Fermi surfaces likely due to antiferromagnetic correlations

Diffraction replicas caused by Bi-O plane modulations

Abstract

On the basis of angle-scanned photoemission data recorded using unpolarised radiation, with high (E,k) resolution, and an extremely dense sampling of k-space, we resolve the current controversy regarding the normal state Fermi surface (FS) in Bi_2Sr_2CaCu_2O_8 (Bi2212). The true picture is simple, self-consistent and robust: the FS is hole-like, with the form of rounded tubes centred on the corners of the Brillouin zone. Two further types of features are also clearly observed: shadow FSs, which are most likely to be due to short range antiferromagnetic spin correlations, and diffraction replicas of the main FS caused by passage of the photoelectrons through the modulated Bi-O planes.