Ferromagnetic kinetic exchange interaction in magnetic insulators

Z.S. Huang, D. Liu, A. Mansikkamaki, V. Vieru, N. Iwahara*, L.F. Chibotaru

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

5 Citations (Web of Science)

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.
Original languageEnglish
Article number033430
Number of pages12
JournalPhysical Review Research
Volume2
Issue number3
DOIs
Publication statusPublished - 16 Sep 2020

Keywords

  • antiferromagnetism
  • complexes
  • crystal
  • electronic-structure
  • hubbard-model
  • orbital physics
  • order
  • superconductivity
  • superexchange interactions
  • transition
  • SUPERCONDUCTIVITY
  • COMPLEXES
  • ANTIFERROMAGNETISM
  • CRYSTAL
  • HUBBARD-MODEL
  • SUPEREXCHANGE INTERACTIONS
  • ORBITAL PHYSICS
  • TRANSITION
  • ORDER
  • ELECTRONIC-STRUCTURE

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