Multipolar ordering and magnetization reversal in two-dimensional nanomagnet arrays.
The low-temperature stable states and the magnetization reversal of realistic two-dimensional nanoarrays with higher-order magnetostatic interactions are studied theoretically. For a general calculus of the multipole-multipole interaction energy we introduce a Hamiltonian in spherical coordinates into the Monte Carlo scheme. We demonstrate that higher-order interactions considerably change the dipolar ground states of in-plane magnetized arrays favoring collinear configurations. The multipolar interactions lead to enhancement or decrease of the coercivity in arrays with in-plane or out-of-plane magnetization.
Vedmedenko
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EY
Institut für Angewandte Physik, Universität Hamburg, Jungiusstrasse 11a, 20355 Hamburg, Germany.
Mikuszeit
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Oepen
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Wiesendanger
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