Importance of matrix elements in the ARPES spectra of BISCO

TL;DR

This study uses first-principles ARPES simulations to show that matrix elements significantly influence the spectral weights in Bi2212, aligning well with experimental observations and emphasizing their importance in high-Tc superconductor analysis.

Contribution

It provides a realistic modeling of ARPES spectra considering full wavefunctions, highlighting the crucial role of matrix elements in interpreting spectral weight variations.

Findings

Spectral weights vary systematically with $k_\parallel$, energy, and photon polarization.

Theoretical results agree with experimental data, confirming matrix element effects.

Matrix elements are essential for accurate ARPES spectrum analysis in high-Tc materials.

Abstract

We have carried out extensive first-principles angle-resolved photointensity (ARPES) simulations in Bi2212 wherein the photoemission process is modelled realistically by taking into account the full crystal wavefunctions of the initial and final states in the presence of the surface. The spectral weight of the ARPES feature associated with the CuO_2 plane bands is found to undergo large and systematic variations with $k_\parallel$ as well as the energy and polarization of the incident photons. These theoretical predictions are in good accord with the corresponding measurements, indicating that the remarkable observed changes in the spectral weights in Bi2212 are essentially a matrix element effect and that the importance of matrix elements should be kept in mind in analyzing the ARPES spectra in the high-Tc's.