Anisotropic Band-Split Magnetism in Magnetostrictive CoFe$_2$O$_4$

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Lane, Harry, Kaur, Guratinder, Kawamata, Masahiro, Nambu, Yusuke, Keller, Lukas, Ewings, Russell A., Voneshen, David J., Williams, Travis J., Walker, Helen C., Viehland, Dwight, Gehring, Peter M., Stock, Chris
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866911324489908224
author Lane, Harry
Kaur, Guratinder
Kawamata, Masahiro
Nambu, Yusuke
Keller, Lukas
Ewings, Russell A.
Voneshen, David J.
Williams, Travis J.
Walker, Helen C.
Viehland, Dwight
Gehring, Peter M.
Stock, Chris
author_facet Lane, Harry
Kaur, Guratinder
Kawamata, Masahiro
Nambu, Yusuke
Keller, Lukas
Ewings, Russell A.
Voneshen, David J.
Williams, Travis J.
Walker, Helen C.
Viehland, Dwight
Gehring, Peter M.
Stock, Chris
contents Single crystal spinel CoFe$_2$O$_4$ exhibits the largest room-temperature saturation magnetostriction among non-rare-earth compounds and a high Curie temperature ($T_c \sim 780$ K), properties that are critical to a wide range of industrial and medical applications. Neutron spectroscopy reveals a large band splitting ($\sim$ 60 meV) between two ferrimagnetic magnon branches, which is driven by site mixing between Co$^{2+}$ and Fe$^{3+}$ cations, and a significantly weaker magnetocrystalline anisotropy ($\sim$ 3 meV). Central to this behavior is the competition between extremely large mismatched molecular fields on the tetrahedral $A$-site and octahedral $B$-site sublattices and the single-ion anisotropy on the $B$-site. This creates a strong energetic anisotropy that locks the magnetic moment within each structural domain in place. As a result of these differing energy scales, switching structural domains is energetically favored over a global spin reorientation under applied magnetic fields, and this is what amplifies the magnetostrictive nature of CoFe$_2$O$_4$.
format Preprint
id arxiv_https___arxiv_org_abs_2512_15683
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Anisotropic Band-Split Magnetism in Magnetostrictive CoFe$_2$O$_4$
Lane, Harry
Kaur, Guratinder
Kawamata, Masahiro
Nambu, Yusuke
Keller, Lukas
Ewings, Russell A.
Voneshen, David J.
Williams, Travis J.
Walker, Helen C.
Viehland, Dwight
Gehring, Peter M.
Stock, Chris
Materials Science
Strongly Correlated Electrons
Single crystal spinel CoFe$_2$O$_4$ exhibits the largest room-temperature saturation magnetostriction among non-rare-earth compounds and a high Curie temperature ($T_c \sim 780$ K), properties that are critical to a wide range of industrial and medical applications. Neutron spectroscopy reveals a large band splitting ($\sim$ 60 meV) between two ferrimagnetic magnon branches, which is driven by site mixing between Co$^{2+}$ and Fe$^{3+}$ cations, and a significantly weaker magnetocrystalline anisotropy ($\sim$ 3 meV). Central to this behavior is the competition between extremely large mismatched molecular fields on the tetrahedral $A$-site and octahedral $B$-site sublattices and the single-ion anisotropy on the $B$-site. This creates a strong energetic anisotropy that locks the magnetic moment within each structural domain in place. As a result of these differing energy scales, switching structural domains is energetically favored over a global spin reorientation under applied magnetic fields, and this is what amplifies the magnetostrictive nature of CoFe$_2$O$_4$.
title Anisotropic Band-Split Magnetism in Magnetostrictive CoFe$_2$O$_4$
topic Materials Science
Strongly Correlated Electrons
url https://arxiv.org/abs/2512.15683