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arXiv · 1703.03228

Spin-wave excitations in the SDW state of iron pnictides: a comparison between the roles of interaction parameters

Dheeraj Kumar Singh
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Abstract

We investigate the role of Hund's coupling in the spin-wave excitations of the ($\pi, 0$) ordered magnetic state within a five-orbital tight-binding model for iron pnictides. To differentiate between the roles of intraorbital Coulomb interaction and Hund's coupling, we focus on the self-consistently obtained mean-field SDW state with a fixed magnetic moment obtained by using different sets of interaction parameters. We find that the Hund's coupling is crucial for the description of various experimentally observed characteristics of the spin-wave excitations including the anisotropy, energy-dependent behavior, and spin-wave spectral weight distribution.

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Dheeraj Kumar Singh. 2017-03-09. Spin-wave excitations in the SDW state of iron pnictides: a comparison between the roles of interaction parameters. https://doi.org/10.1063/1.4998743

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