Low-Frequency Dynamic Magnetic Susceptibility of Antiferromagnetic Nanoparticles with Superparamagnetic Properties
As is known, the multi-sublattice structure of antiferromagnets (AFMs) entails that, under size diminution to the nanoscale, compensation of the sublattice magnetizations becomes incomplete. Due to that, the nanoparticles acquire small, but finite permanent magnetic moments. An AC field applied to s...
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| Format: | Article |
| Language: | English |
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MDPI AG
2022-10-01
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| Series: | Magnetism |
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| Online Access: | https://www.mdpi.com/2673-8724/2/4/24 |
| _version_ | 1827638002952699904 |
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| author | Igor S. Poperechny Yuriy L. Raikher |
| author_facet | Igor S. Poperechny Yuriy L. Raikher |
| author_sort | Igor S. Poperechny |
| collection | DOAJ |
| description | As is known, the multi-sublattice structure of antiferromagnets (AFMs) entails that, under size diminution to the nanoscale, compensation of the sublattice magnetizations becomes incomplete. Due to that, the nanoparticles acquire small, but finite permanent magnetic moments. An AC field applied to such particles induces their magnetic response, the measurement of which is well within the sensitivity range of the experimental technique. Given the small size of the particles, their magnetodynamics is strongly affected by thermal fluctuations, so that their response bears a considerable superparamagnetic contribution. This specific feature is well-known, but usually is accounted for at the estimation accuracy level. Herein, a kinetic model is proposed to account for the magnetic relaxation of AFM nanoparticles, i.e., the processes that take place in the frequency domain well below the magnetic resonance band. Assuming that the particles possess uniaxial magnetic anisotropy, the expressions for the principal components of the both linear static and dynamic susceptibilities are derived, yielding simple analytical expressions, including those for the case of a random distribution of the particle axes. |
| first_indexed | 2024-03-09T16:10:33Z |
| format | Article |
| id | doaj.art-f5705330d4a548bba0008655051b25e5 |
| institution | Directory Open Access Journal |
| issn | 2673-8724 |
| language | English |
| last_indexed | 2024-03-09T16:10:33Z |
| publishDate | 2022-10-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Magnetism |
| spelling | doaj.art-f5705330d4a548bba0008655051b25e52023-11-24T16:18:14ZengMDPI AGMagnetism2673-87242022-10-012434035510.3390/magnetism2040024Low-Frequency Dynamic Magnetic Susceptibility of Antiferromagnetic Nanoparticles with Superparamagnetic PropertiesIgor S. Poperechny0Yuriy L. Raikher1Institute of Continuous Media Mechanics, Russian Academy of Sciences, Ural Branch, 614018 Perm, RussiaInstitute of Continuous Media Mechanics, Russian Academy of Sciences, Ural Branch, 614018 Perm, RussiaAs is known, the multi-sublattice structure of antiferromagnets (AFMs) entails that, under size diminution to the nanoscale, compensation of the sublattice magnetizations becomes incomplete. Due to that, the nanoparticles acquire small, but finite permanent magnetic moments. An AC field applied to such particles induces their magnetic response, the measurement of which is well within the sensitivity range of the experimental technique. Given the small size of the particles, their magnetodynamics is strongly affected by thermal fluctuations, so that their response bears a considerable superparamagnetic contribution. This specific feature is well-known, but usually is accounted for at the estimation accuracy level. Herein, a kinetic model is proposed to account for the magnetic relaxation of AFM nanoparticles, i.e., the processes that take place in the frequency domain well below the magnetic resonance band. Assuming that the particles possess uniaxial magnetic anisotropy, the expressions for the principal components of the both linear static and dynamic susceptibilities are derived, yielding simple analytical expressions, including those for the case of a random distribution of the particle axes.https://www.mdpi.com/2673-8724/2/4/24antiferromagnetic nanoparticlesuncompensated magnetic momentsuperparamagnetismAC probinglow-frequency magnetic susceptibility |
| spellingShingle | Igor S. Poperechny Yuriy L. Raikher Low-Frequency Dynamic Magnetic Susceptibility of Antiferromagnetic Nanoparticles with Superparamagnetic Properties Magnetism antiferromagnetic nanoparticles uncompensated magnetic moment superparamagnetism AC probing low-frequency magnetic susceptibility |
| title | Low-Frequency Dynamic Magnetic Susceptibility of Antiferromagnetic Nanoparticles with Superparamagnetic Properties |
| title_full | Low-Frequency Dynamic Magnetic Susceptibility of Antiferromagnetic Nanoparticles with Superparamagnetic Properties |
| title_fullStr | Low-Frequency Dynamic Magnetic Susceptibility of Antiferromagnetic Nanoparticles with Superparamagnetic Properties |
| title_full_unstemmed | Low-Frequency Dynamic Magnetic Susceptibility of Antiferromagnetic Nanoparticles with Superparamagnetic Properties |
| title_short | Low-Frequency Dynamic Magnetic Susceptibility of Antiferromagnetic Nanoparticles with Superparamagnetic Properties |
| title_sort | low frequency dynamic magnetic susceptibility of antiferromagnetic nanoparticles with superparamagnetic properties |
| topic | antiferromagnetic nanoparticles uncompensated magnetic moment superparamagnetism AC probing low-frequency magnetic susceptibility |
| url | https://www.mdpi.com/2673-8724/2/4/24 |
| work_keys_str_mv | AT igorspoperechny lowfrequencydynamicmagneticsusceptibilityofantiferromagneticnanoparticleswithsuperparamagneticproperties AT yuriylraikher lowfrequencydynamicmagneticsusceptibilityofantiferromagneticnanoparticleswithsuperparamagneticproperties |