Ferromagnetic kinetic exchange interaction in magnetic insulators
Huang, Zhishuo; Liu, Dan; Mansikkamäki, Akseli; Vieru, Veacheslav; Iwahara, Naoya; Chibotaru, Liviu F. (2020-09-16)
Huang, Z., Liu, D., Mansikkamäki, A., Vieru, V., Iwahara, N., Chibotaru, L. (2020) Ferromagnetic kinetic exchange interaction in magnetic insulators. Physical Review Research, 2 (3), 033430. https://doi.org/10.1103/PhysRevResearch.2.033430
© The Authors. Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.
https://creativecommons.org/licenses/by/4.0/
https://urn.fi/URN:NBN:fi-fe2020092976165
Tiivistelmä
Abstract
The superexchange theory predicts dominant antiferromagnetic kinetic interaction when the orbitals accommodating magnetic electrons are covalently bonded through diamagnetic bridging atoms or groups. Here we show that explicit consideration of magnetic and (leading) bridging orbitals, together with the electron transfer between the former, reveals a strong ferromagnetic kinetic exchange contribution. First-principles calculations show that it is comparable in strength with antiferromagnetic superexchange in a number of magnetic materials with diamagnetic metal bridges. In particular, it is responsible for a very large ferromagnetic coupling (−10 meV) between the iron ions in a Fe³⁺−Co³⁺−Fe³⁺ complex. Furthermore, we find that the ferromagnetic exchange interaction turns into antiferromagnetic by substituting the diamagnetic bridge with magnetic one. The phenomenology is observed in two series of materials, supporting the significance of the ferromagnetic kinetic exchange mechanism.
Kokoelmat
- Avoin saatavuus [34609]