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An accurate effective action for `baby' to `adult' skyrmions

Kyungsun Moon·Kieran Mullen
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Abstract

Starting with a Chern-Simons theory, we derive an effective action for interacting quantum Hall skyrmions that takes into account both large-distance physics and short-distance details as well. We numerically calculate the classical static skyrmion profile from this action and find excellent agreement with other, microscopic calculations over a wide range of skyrmion sizes including the experimentally relevant one. This implies that the essential physics of this regime might be captured by a continuum classical model rather than resorting to more microscopic approaches. We also show that the skyrmion energy closely follows the formula suggested earlier by Sondhi et al. for a broad parameter range of interest as well.

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Kyungsun Moon, Kieran Mullen. 1997-07-23. An accurate effective action for `baby' to `adult' skyrmions. https://doi.org/10.1103/physrevb.57.14833

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