First- principle calculations of magnetic interactions in correlated systems

TL;DR

This paper introduces a new first-principles method to calculate magnetic interactions in correlated systems, incorporating realistic electronic structures and local correlation effects, validated through calculations on ferromagnetic iron.

Contribution

It develops a novel approach for computing magnetic interaction parameters in correlated materials using a local, frequency-dependent self-energy framework.

Findings

Successfully derived expressions for exchange interactions, Dzialoshinskii-Moriya interaction, and magnetic anisotropy.

Performed first-principles calculations of magnetic spectra for ferromagnetic iron.

Incorporated local correlation effects via QMC scheme into magnetic property calculations.

Abstract

We present a novel approach to calculate the effective exchange interaction parameters based on the realistic electronic structure of correlated magnetic crystals in local approach with the frequency dependent self energy. The analog of ``local force theorem'' in the density functional theory is proven for highly correlated systems. The expressions for effective exchange parameters, Dzialoshinskii- Moriya interaction, and magnetic anisotropy are derived. The first-principle calculations of magnetic excitation spectrum for ferromagnetic iron, with the local correlation effects from the numerically exact QMC-scheme is presented.