title: Thermal string excitations in artificial spin-ice square dipolar array.
abstract: We report on a theoretical investigation of artificial spin-ice dipolar arrays using a nanoisland shape adopted from recent experiments (Farhan et al 2013 Nature Phys. 9 375). The number of thermal magnetic string excitations in the square lattice is drastically increased by a vertical displacement of rows and columns. We find large increments especially for low temperatures and for string excitations with quasi-monopoles of charges ± 4. By kinetic Monte Carlo simulations we address the thermal stability of such excitations, thereby providing time scales for their experimental observation.
authors.forename: D
authors.initials: D
authors.lastname: Thonig
authors.forename: S
authors.initials: S
authors.lastname: Reißaus
authors.forename: I
authors.initials: I
authors.lastname: Mertig
authors.forename: J
authors.initials: J
authors.lastname: Henk