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arXiv · 0707.1582

Stripe width and non-local domain walls in the two-dimensional Dipolar Frustrated Ising Ferromagnet

Alessandro Vindigni·Niculin Saratz·Oliver Portmann·Danilo Pescia·Paolo Politi
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Abstract

We describe a novel type of magnetic domain wall which, in contrast to Bloch or Neel walls, is non-localized and, in a certain temperature range, non-monotonic. The wall appears as the mean-field solution of the two-dimensional ferromagnetic Ising model frustrated by the long-ranged dipolar interaction. We provide experimental evidence of this wall delocalization in the stripe-domain phase of perpendicularly magnetized ultrathin magnetic films. In agreement with experimental results, we find that the stripe width decreases with increasing temperature and approaches a finite value at the Curie-temperature following a power law. The same kind of wall and a similar temperature dependence of the stripe width is expected in the mean-field approximation of the two-dimensional Coulomb frustrated Ising ferromagnet.

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Alessandro Vindigni, Niculin Saratz, Oliver Portmann, Danilo Pescia, Paolo Politi. 2008-02-29. Stripe width and non-local domain walls in the two-dimensional Dipolar Frustrated Ising Ferromagnet. https://doi.org/10.1103/physrevb.77.092414

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