Theory of Angle Resolved Photoemission Spectroscopy of Altermagnetic Mott Insulators

TL;DR

This paper develops a theoretical framework for ARPES response in altermagnetic Mott insulators, revealing a magnetic polaron with spin-dependent spectral features and confirming predictions with tensor network simulations.

Contribution

It introduces a spinon-holon parton theory for altermagnetic Mott insulators and predicts a renormalized bandwidth and characteristic spectral features.

Findings

Prediction of a renormalized bandwidth confirmed by tensor network simulations.

Identification of a spin-dependent spectral weight of the magnetic polaron.

Analysis of the characteristic spin-split spectrum due to altermagnetic symmetry.

Abstract

Altermagnetism has emerged as an unconventional form of collinear magnetism with spatial rotational symmetries, that give rise to strongly spin-split bands despite of an underlying fully-compensated antiferromagnetic order. Here, we develop a theory for the Angle Resolved Photoemission Spectroscopy (ARPES) response of altermagnetic Mott insulators. Crucially, the spectrum does not simply reflect the non-interacting band structure, but instead a magnetic polaron is formed at low energies, that can be interpreted as a spinon-holon bound state. We develop a spinon-holon parton theory and predict a renormalized bandwidth that we confirm by tensor network simulations. We analyze the characteristic spin-split spectrum and identify a spin-dependent spectral weight of the magnetic polaron, resulting from the altermagnetic symmetry. Our work paves the way for a systematic study of doping effects and correlation phenomena in altermagnetic Mott insulators.