Domain-wall free energy in Heisenberg ferromagnets

Boris Sangiorgio; Thomas C. T. Michaels; Danilo Pescia; Alessandro Vindigni

doi:10.1103/physrevb.89.014429

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arXiv · 1308.3984

Domain-wall free energy in Heisenberg ferromagnets

Boris Sangiorgio·Thomas C. T. Michaels·Danilo Pescia·Alessandro Vindigni

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Abstract

We consider Gaussian fluctuations about domain walls embedded in one- or two-dimensional spin lattices. Analytic expressions for the free energy of one domain wall are obtained. From these, the temperature dependence of experimentally relevant spatial scales -- i.e., the correlation length for spin chains and the size of magnetic domains for thin films magnetized out of plane -- are deduced. Stability of chiral order inside domain walls against thermal fluctuations is also discussed.

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Boris Sangiorgio, Thomas C. T. Michaels, Danilo Pescia, Alessandro Vindigni. 2013-08-19. Domain-wall free energy in Heisenberg ferromagnets. https://doi.org/10.1103/physrevb.89.014429

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