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On the ground states of an array of magnetic dots in the vortex state and subject to a normal magnetic field

J. E. L. Bishop·A. Yu. Galkin·B. A. Ivanov
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Abstract

Dipole-dipole interactions in a square planar array of sub-micron magnetic disks (magnetic dots) have been studied theoretically. Under a normal magnetic field the ground-state of the array undergoes many structural transitions between the limiting chessboard antiferromagnetic state at zero field and the ferromagnet at a threshold field. At intermediate fields, numerous ferrimagnetic states having mean magnetic moments between zero and that of the ferromagnetic state are favorable energetically. The structures and energies of a selection of states are calculated and plotted, as are the fields required to optimally reverse the magnetic moment of a single dot within them. Approximate formulae for the dipolar energy and anhysteretic magnetization curve are presented.

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J. E. L. Bishop, A. Yu. Galkin, B. A. Ivanov. 2001-11-12. On the ground states of an array of magnetic dots in the vortex state and subject to a normal magnetic field. https://arxiv.org/abs/cond-mat/0111225

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