Fermi Surfaces, Fermi Patches, and Fermi Arcs in High Tc Superconductors

TL;DR

This paper analyzes ARPES data on high-Tc cuprates, proposing a new picture of patches and arcs in momentum space that could be key to understanding their superconducting properties.

Contribution

It introduces a novel interpretation of Fermi surface features in cuprates, emphasizing patches and arcs over the conventional Fermi surface concept.

Findings

Patches are dispersionless and interaction-dominated regions.

Fermi arcs are disconnected regions in the pseudogap phase.

Patches are gapped out in the pseudogap phase, leaving arcs.

Abstract

A defining property of metals is the existence of a Fermi surface: for two dimensions, a continuous contour in momentum space which separates occupied from unoccupied states. In this paper, I discuss angle resolved photoemission data on the cuprate superconductor BSCCO and argue that it is not best thought of in this conventional picture. Rather, the data are consistent with ``patches'' of finite area connected by more conventional ``arcs''. Novel physics is associated with the patches, in that the states contained in a patch are dispersionless and thus interaction dominated. In the pseudogap phase, the patches are gapped out, leaving the Fermi arcs disconnected. This unusual situation may be the key to understanding the microscopic physics of the high temperature superconductors, in that the pairing correlations are strongest in the patches, yet the superfluid density lives only on the arcs.