Optical Process of Linear Dichroism in Angle-Resolved Core-Level Photoemission Reflecting Strongly Correlated Anisotropic Orbital Symmetry

TL;DR

This paper revisits the theoretical framework and simulations of angular distributions in polarization-dependent core-level photoemission spectra to explain the observed linear dichroism in 4f-based rare-earth compounds, emphasizing the role of orbital symmetry.

Contribution

It provides a detailed formulation and simulation approach to understand linear dichroism in core-level photoemission, highlighting the importance of core d-level excitations in localized ions with cubic symmetry.

Findings

Core d-level excitations are crucial for linear dichroism in cubic symmetry ions.

Simulations align with experimental observations of LD in rare-earth compounds.

Orbital symmetry determines the presence of LD in core-level photoemission.

Abstract

We revisit the formulations and simulations of angular distributions in polarization-dependent core-level photoemission spectra of strongly correlated electron systems, in order to explain the recently discovered linear dichroism (LD) in the core-level photoemission of 4f-based rare-earth compounds. Owing to the selection rules for the optical process of core-level excitations, the LD originating from the anisotropic outer localized charge distributions determined by the ground-state orbital symmetry can be observed. Our simulations show that core d-level excitations are essential for the LD in localized ions having a cubic symmetry, which is absent in the p-orbital excitations.