Magnetic octupoles as the order parameter for unconventional antiferromagnetism

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Bhowal, Sayantika, Spaldin, Nicola A.
Natura: Preprint
Pubblicazione: 2022
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866918048449953792
author Bhowal, Sayantika
Spaldin, Nicola A.
author_facet Bhowal, Sayantika
Spaldin, Nicola A.
contents We show that time-reversal symmetry broken, centrosymmetric antiferromagnets with nonrelativistic spin-splitting are conveniently described in terms of the ferroic ordering of magnetic octupoles. The magnetic octupoles are the lowest-order ferroically ordered magnetic quantity in this case, and so are the natural order parameter for the transition into the magnetically ordered state. They provide a unified description of the broken time-reversal symmetry and the non-relativistic spin splitting as well as a platform for manipulating the latter, and account for other phenomena, such as piezomagnetism, characteristic of this class of antiferromagnets. Unusually for antiferromagnets, we show that the magnetic octupoles cause a non-zero magnetic Compton scattering, providing a route for their direct experimental detection. We illustrate these concepts using density-functional and model calculations for the prototypical non-relativistic spin-split antiferromagnet, rutile-structure manganese difuoride, MnF2.
format Preprint
id arxiv_https___arxiv_org_abs_2212_03756
institution arXiv
publishDate 2022
record_format arxiv
spellingShingle Magnetic octupoles as the order parameter for unconventional antiferromagnetism
Bhowal, Sayantika
Spaldin, Nicola A.
Strongly Correlated Electrons
Materials Science
We show that time-reversal symmetry broken, centrosymmetric antiferromagnets with nonrelativistic spin-splitting are conveniently described in terms of the ferroic ordering of magnetic octupoles. The magnetic octupoles are the lowest-order ferroically ordered magnetic quantity in this case, and so are the natural order parameter for the transition into the magnetically ordered state. They provide a unified description of the broken time-reversal symmetry and the non-relativistic spin splitting as well as a platform for manipulating the latter, and account for other phenomena, such as piezomagnetism, characteristic of this class of antiferromagnets. Unusually for antiferromagnets, we show that the magnetic octupoles cause a non-zero magnetic Compton scattering, providing a route for their direct experimental detection. We illustrate these concepts using density-functional and model calculations for the prototypical non-relativistic spin-split antiferromagnet, rutile-structure manganese difuoride, MnF2.
title Magnetic octupoles as the order parameter for unconventional antiferromagnetism
topic Strongly Correlated Electrons
Materials Science
url https://arxiv.org/abs/2212.03756