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Magnons and skyrmions in fractional Hall ferromagnets

A. H. MacDonald·J. J. Palacios
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Abstract

Recent experiments have established a qualitative difference between the magnetization temperature-dependences $M(T)$ of quantum Hall ferromagnets at integer and fractional filling factors. We explain this difference in terms of the relative energies of collective magnon and particle-hole excitations in the two cases. Analytic calculations for hard-core model systems are used to demonstrate that, in the fractional case, interactions suppress the magnetization at finite temperatures and that particle-hole excitations rather than long-wavelength magnons control $M(T)$ at low $T$.

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A. H. MacDonald, J. J. Palacios. 1998-06-06. Magnons and skyrmions in fractional Hall ferromagnets. https://doi.org/10.1103/physrevb.58.r10171

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