## Abstract

We analyze the momentum and temperature dependences of the magnetic susceptibilities and magnetic exchange interaction in paramagnetic bcc iron by a combination of density functional theory and dynamical mean-field theory (DFT+DMFT). By considering a general derivation of the orbital-resolved effective model for spin degrees of freedom for Hund's metals, we relate momentum-dependent susceptibilities in the paramagnetic phase to the magnetic exchange. We then calculate nonuniform orbital-resolved susceptibilities at high-symmetry wave vectors by constructing appropriate supercells in the DMFT approach. Extracting the irreducible parts of susceptibilities with respect to Hund's exchange interaction, we determine the corresponding orbital-resolved exchange interactions, which are then interpolated to the whole Brillouin zone. Using the spherical model we estimate the temperature dependence of the resulting exchange between local moments.

Original language | English |
---|---|

Article number | 075108 |

Journal | Physical Review B |

Volume | 96 |

Issue number | 7 |

DOIs | |

Publication status | Published - 7 Aug 2017 |

Externally published | Yes |