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arXiv · 1204.4848

Collapse of Skyrmions in 2d Ferro- and Antiferromagnets

Liufei Cai·Eugene M. Chudnovsky·D. A. Garanin
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Abstract

Collapse of a skyrmion due to the discreteness of a crystal lattice in isotropic two-dimensional ferro- and antiferromagnets has been studied analytically and by numerical solution of equations of motion for up to 2000 x 2000 classical spins on a square lattice coupled via Heisenberg exchange interaction. Excellent agreement between analytical and numerical results has been achieved. The lifetime of the skyrmion scales with its initial size, lambda_0, as(lambda_0/a)^5 in ferromagnets and as (lambda_0/a)^2.15 in antiferromagnets, with a being the lattice parameter. This makes antiferromagnetic skyrmions significantly shorter lived than ferromagnetic skyrmions.

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Liufei Cai, Eugene M. Chudnovsky, D. A. Garanin. 2012-04-21. Collapse of Skyrmions in 2d Ferro- and Antiferromagnets. https://doi.org/10.1103/physrevb.86.024429

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