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Domain wall roughening in dipolar films in the presence of disorder

Jaime E. Santos·Erwin Frey·Franz Schwabl
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Abstract

We derive a low-energy Hamiltonian for the elastic energy of a Néel domain wall in a thin film with in-plane magnetization, where we consider the contribution of the long-range dipolar interaction beyond the quadratic approximation. We show that such a Hamiltonian is analogous to the Hamiltonian of a one-dimensional polaron in an external random potential. We use a replica variational method to compute the roughening exponent of the domain wall for the case of two-dimensional dipolar interactions.

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Jaime E. Santos, Erwin Frey, Franz Schwabl. 2002-03-27. Domain wall roughening in dipolar films in the presence of disorder. https://doi.org/10.1103/physreve.65.031608

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