Theoretical calculation of magnetic damping

Magnetic damping is a key parameter that quantifies energy dissipation in magnetization dynamics. It directly impacts device performance by determining the writing speed of magnetic recording media and the switching current required in spin-transfer-torque devices. Since standard density functional theory packages do not provide direct damping evaluation, we developed a first-principles code based on the torque-correlation model for quantitative damping calculations from electronic-structure results.

Our code is designed for practical materials exploration: it includes the virtual crystal approximation (VCA) for alloy systems and can be applied to both bulk materials and multilayer supercells. Using this framework, we investigated finite-temperature effects on intrinsic damping in FePt. We found that lattice vibrations slightly enhance damping near the Curie temperature, indicating that strong damping reduction observed experimentally at high temperature is likely dominated by extrinsic mechanisms.

We also investigated damping and magnetostriction in Fe4N-based alloys. For (Fe1-xCox)4N, we reproduced experimental trends using an electron-doping picture and found a correlation between the sign of magnetostriction and damping magnitude. This trend is consistent with fcc-(Ni1-yCoy) alloys and with the long-standing behavior of permalloy. These results suggest that Fermi-level tuning relative to minority-spin density-of-states peaks can simultaneously control damping and magnetostriction.

Temperature dependence of FePt damping due to atomic vibration.

Calculated damping versus magnetostriction for (Fe1-xCox)4N.

(Kurniawan et al., 2023)
(Ito et al., 2025)
(Kurniawan et al., 2025)

References

2025

Giant tunability of magnetoelasticity in Fe4N system as a platform to unveil correlation between magnetostriction and magnetic damping

Keita Ito , Ivan Kurniawan, Yusuke Shimada , Yoshio Miura, Yasushi Endo , and Takeshi Seki

Commun. Mater., Mar 2025

DOI Bib

@article{Ito2025-mp,
  title = {Giant tunability of magnetoelasticity in {Fe4N} system as a
                 platform to unveil correlation between magnetostriction and
                 magnetic damping},
  author = {Ito, Keita and Kurniawan, Ivan and Shimada, Yusuke and Miura, Yoshio and Endo, Yasushi and Seki, Takeshi},
  journal = {Commun. Mater.},
  publisher = {Nature Publishing Group},
  volume = {6},
  number = {53},
  pages = {53},
  month = mar,
  year = {2025},
  doi = {10.1038/s43246-025-00784-5},
  issn = {2662-4443,2662-4443},
  language = {en},
}

Microscopic correlation between magnetostriction and magnetic damping

Ivan Kurniawan, Keita Ito , Takeshi Seki , Keisuke Masuda, and Yoshio Miura

Phys. Rev. B., Sep 2025

DOI arXiv Bib

@article{Kurniawan2025-gz,
  title = {Microscopic correlation between magnetostriction and magnetic
                 damping},
  author = {Kurniawan, Ivan and Ito, Keita and Seki, Takeshi and Masuda, Keisuke and Miura, Yoshio},
  journal = {Phys. Rev. B.},
  publisher = {American Physical Society (APS)},
  volume = {112},
  number = {10},
  month = sep,
  year = {2025},
  doi = {10.1103/g47q-qyxj},
  issn = {2469-9950,2469-9969},
  language = {en},
}

2023

Theoretical study of the effect of lattice dynamics on the damping constant of FePt at finite temperature

Ivan Kurniawan, Yoshio Miura, Guangzong Xing, Terumasa Tadano, and Kazuhiro Hono

Phys. Rev. B, Sep 2023

DOI Bib

@article{Kurniawan2023-vq,
  title = {Theoretical study of the effect of lattice dynamics on the
                 damping constant of {FePt} at finite temperature},
  author = {Kurniawan, Ivan and Miura, Yoshio and Xing, Guangzong and Tadano, Terumasa and Hono, Kazuhiro},
  journal = {Phys. Rev. B},
  publisher = {American Physical Society,},
  volume = {108},
  number = {9},
  pages = {094426},
  month = sep,
  year = {2023},
  issn = {0163-1829},
  doi = {10.1103/PhysRevB.108.094426},
}