title: Multipolar ordering and magnetization reversal in two-dimensional nanomagnet arrays.
abstract: 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.
authors.affiliation: Institut für Angewandte Physik, Universität Hamburg, Jungiusstrasse 11a, 20355 Hamburg, Germany.
authors.forename: E Y
authors.initials: EY
authors.lastname: Vedmedenko
authors.forename: N
authors.initials: N
authors.lastname: Mikuszeit
authors.forename: H P
authors.initials: HP
authors.lastname: Oepen
authors.forename: R
authors.initials: R
authors.lastname: Wiesendanger