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Nonanalytic Corrections to Fermi-Liquid Behavior in Helimagnets

T. R. Kirkpatrick·D. Belitz
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Abstract

The Goldstone mode in the ordered phase of itinerant helimagnets, such as MnSi or FeGe, is determined and shown to have a strongly anisotropic dispersion relation. The softness of this mode is, in a well-defined sense, in between that of ferromagnetic and antiferromagnetic magnons, respectively. It is shown that this soft mode leads to nonanalytic corrections to Fermi-liquid behavior, with a T-contribution to the specific heat coefficient, and a T^{5/2}-contribution to the resistivity. The quasi-particle inelastic lifetime shows anisotropic behavior in momentum space.

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T. R. Kirkpatrick, D. Belitz. 2005-06-29. Nonanalytic Corrections to Fermi-Liquid Behavior in Helimagnets. https://doi.org/10.1103/physrevb.72.180402

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