Phys. Rev. Lett. Phys. Rev. A Phys. Rev. B Phys. Rev. C Phys. Rev. D Phys. Rev. E Phys. Rev. ST AB Rev. Mod. Phys. Phys. Rev. (Series I) Phys. Rev. Volume: Page/Article:

Phys. Rev. B 33, 6281–6286 (1986)

[Issue 9 – 1 May 1986 ]

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Dynamics of branched domain structures

M. Gabay and T. Garel

Laboratoire de Physique des Solides, Btiment 510, Université ParisSud, Centre d'Orsay, 91405 Orsay Cédex, France

We consider Ising dipolar ferromagnets in a simple geometry (infinite slab of thickness D). When D increases, these systems undergo phase transitions characterized by the appearance of branched domain structures. We have studied the field-induced distortions of the highly branched case, in the framework of the self-similar Privorotskii model. This enables us to calculate the response of the system to a small field step, using a constrained dynamical model of Palmer et al. Relaxations follow a lnt law. This behavior is to be contrasted to the stripe (unbranched) case, where a usual exponential relaxation is obtained. This slowing down can be traced back to the existence of many length scales in the branched regime. Analogous results should hold for dipolar metamagnets.

©1986 The American Physical Society

URL: http://link.aps.org/abstract/PRB/v33/p6281
DOI: 10.1103/PhysRevB.33.6281
PACS: 75.30.Kz, 75.50.Ee, 75.60.Ch

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