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Magnons in real materials from density-functional theory

Ralph Gebauer·Stefano Baroni
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Abstract

We present an implementation of the adiabatic spin-wave dynamics of Niu and Kleinman. This technique allows to decouple the spin and charge excitations of a many-electron system using a generalization of the adiabatic approximation. The only input for the spin-wave equations of motion are the energies and Berry curvatures of many-electron states describing frozen spin spirals. The latter are computed using a newly developed technique based on constrained density-functional theory, within the local spin density approximation and the pseudo-potential plane-wave method. Calculations for iron show an excellent agreement with experiments.

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Ralph Gebauer, Stefano Baroni. 1999-08-26. Magnons in real materials from density-functional theory. https://doi.org/10.1103/physrevb.61.r6459

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