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arXiv · 1611.06171

Composite Spin Crystal Phase in Antiferromagnetic Chiral Magnets

S. A. Osorio·H. D. Rosales·M. B. Sturla·D. C. Cabra
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Abstract

We study the classical antiferromagnetic Heisenberg model on the triangular lattice with Dzyaloshinskii-Moriya interactions in a magnetic field. We focus in particular in the emergence of a composite spin crystal phase, dubbed antiferromagnetic skyrmion lattice, that was recently observed in [Phys. Rev. B 92, 214439 (2015)] for intermediate fields. This complex phase can be made up from three inter-penetrated skyrmion lattices, one for each sub-lattice of the original triangular one. Following these recent numerical results, in this paper we explicitly construct the low-energy effective action that reproduces the correct phenomenology and could serve as a starting point to study the coupling to charge carriers, lattice vibrations, structural disorder and transport phenomena.

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S. A. Osorio, H. D. Rosales, M. B. Sturla, D. C. Cabra. 2016-11-18. Composite Spin Crystal Phase in Antiferromagnetic Chiral Magnets. https://doi.org/10.1103/physrevb.96.024404

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