Theory of the waterfall phenomenon in cuprate superconductors

TL;DR

This paper explains the waterfall phenomenon in cuprate superconductors' ARPES spectra as a destructive interference effect linked to Zhang-Rice singlets, connecting charge transfer and single band Hubbard models.

Contribution

It provides a theoretical explanation for the waterfall phenomenon using exact diagonalization and variational cluster approximation calculations.

Findings

Waterfall phenomenon arises from interference between O2p orbitals and photohole phases.

The phenomenon visualizes the Zhang-Rice singlet construction.

Connects charge transfer models with single band Hubbard models.

Abstract

Based on exact diagonalization and variational cluster approximation calculations we study the relationship between charge transfer models and the corresponding single band Hubbard models. We present an explanation for the waterfall phenomenon observed in angle resolved photoemission spectroscopy (ARPES) on cuprate superconductors. The phenomenon is due to the destructive interference between the phases of the O2p orbitals belonging to a given Zhang-Rice singlet and the Bloch phases of the photohole which occurs in certain regions of k-space. It therefore may be viewed as a direct experimental visualisation of the Zhang-Rice construction of an effective single band model for the CuO2 plane.