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arXiv · 1304.1983

Phenomenological model of anomalous magnon softening and damping in half-metallic manganites

A. Solontsov
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Abstract

To describe anomalous zone-boundary softening and damping of magnons in manganites we present a phenomenological two-fluid model containing ferromagnetic Fermi-liquid and non-Fermi-liquid components. The Fermi-liquid component accounts for softening of zone-boundary magnons and for the Landau damping of magnons in the Stoner continuum arising at low frequencies due to zero-point effects. Coupling of the Fermi-liquid and non-Fermi-liquid fluids yields conventional long wavelength magnons damped due to their coupling with longitudinal spin fluctuations.

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A. Solontsov. 2013-04-07. Phenomenological model of anomalous magnon softening and damping in half-metallic manganites. https://doi.org/10.1103/physrevb.88.104402

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