Understanding electronic excited states in BiFeO$_3$ via ab initio calculations and symmetry analysis

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Kshirsagar, Aseem Rajan, Reichardt, Sven
Natura: Preprint
Pubblicazione: 2024
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866916441213632512
author Kshirsagar, Aseem Rajan
Reichardt, Sven
author_facet Kshirsagar, Aseem Rajan
Reichardt, Sven
contents BiFeO$_3$ is a technologically relevant multiferroic perovskite featuring ferroelectricity and antiferromagnetism. Its lattice, magnetic, and ferroelectric degrees of freedoms are coupled to its optically active excitations and thus hold the potential to be reversible probed and controlled by light. In this work, we combine ab initio density functional and many-body perturbation theory methods with an extensive symmetry and atomic-orbital analysis to describe and understand the electronic excited states spectrum and its imprint on the optical absorption spectrum with quantitative accuracy and qualitative insights. We find that the optical absorption spectrum of BiFeO$_3$ contain several strongly bound and spatially localized electronic transitions in which the spin-degree of freedom is almost fully flipped. With our analysis we thoroughly characterize these localized spin-flip transitions in terms of the unusual crystal field splitting of Fe-$3d$ single-electron orbitals. Our symmetry analysis further allows us to thoroughly explain how the spin content and the energetic fine structure of these strongly bound excitons are dictated by the interplay between crystal symmetry, electron-hole attraction, and the spin-orbit coupling.
format Preprint
id arxiv_https___arxiv_org_abs_2402_05542
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Understanding electronic excited states in BiFeO$_3$ via ab initio calculations and symmetry analysis
Kshirsagar, Aseem Rajan
Reichardt, Sven
Materials Science
Mesoscale and Nanoscale Physics
BiFeO$_3$ is a technologically relevant multiferroic perovskite featuring ferroelectricity and antiferromagnetism. Its lattice, magnetic, and ferroelectric degrees of freedoms are coupled to its optically active excitations and thus hold the potential to be reversible probed and controlled by light. In this work, we combine ab initio density functional and many-body perturbation theory methods with an extensive symmetry and atomic-orbital analysis to describe and understand the electronic excited states spectrum and its imprint on the optical absorption spectrum with quantitative accuracy and qualitative insights. We find that the optical absorption spectrum of BiFeO$_3$ contain several strongly bound and spatially localized electronic transitions in which the spin-degree of freedom is almost fully flipped. With our analysis we thoroughly characterize these localized spin-flip transitions in terms of the unusual crystal field splitting of Fe-$3d$ single-electron orbitals. Our symmetry analysis further allows us to thoroughly explain how the spin content and the energetic fine structure of these strongly bound excitons are dictated by the interplay between crystal symmetry, electron-hole attraction, and the spin-orbit coupling.
title Understanding electronic excited states in BiFeO$_3$ via ab initio calculations and symmetry analysis
topic Materials Science
Mesoscale and Nanoscale Physics
url https://arxiv.org/abs/2402.05542