Extracting the spectral function of the cuprates by a full two-dimensional analysis: Angle-resolved photoemission spectra of Bi2Sr2CuO6

TL;DR

This study introduces a comprehensive two-dimensional analysis method for ARPES data, enabling detailed extraction of the spectral function and self-energy of Bi2Sr2CuO6, revealing insights into high-energy anomalies in cuprates.

Contribution

A new two-dimensional fitting scheme for ARPES data is developed and applied to extract the spectral function and self-energy across a broad energy and momentum range in cuprates.

Findings

Spectral function can be modeled with few tight-binding parameters and a weakly-momentum-dependent self-energy.

The analysis extends up to 0.7 eV in binding energy across the entire Brillouin zone.

Estimated momentum dependence of the matrix element is obtained.

Abstract

Recently, angle-resolved photoemission spectroscopy (ARPES) has revealed a dispersion anomaly at high binding energy near 0.3-0.5eV in various families of the high-temperature superconductors. For further studies of this anomaly we present a new two-dimensional fitting-scheme and apply it to high-statistics ARPES data of the strongly-overdoped Bi2Sr2CuO6 cuprate superconductor. The procedure allows us to extract theself-energy in an extended energy and momentum range. It is found that the spectral function of Bi2Sr2CuO6 can be parameterized using a small set of tight-binding parameters and a weakly-momentum-dependent self-energy up to 0.7 eV in binding energy and over the entire first Brillouin zone. Moreover the analysis gives an estimate of the momentum dependence of the matrix element, a quantity, which is often neglected in ARPES analyses.