Correlated magnetic vortex chains in mesoscopic cobalt dot arrays.

Phys Rev Lett

Laboratoire de Photonique et Nanostructures LPN-CNRS, Route de Nozay, 91460 Marcoussis, France.

Published: April 2002

Nucleation and annihilation of vortex states have been studied in two-dimensional arrays of densely packed cobalt dots. A clear signature of dipolar interactions both between single-domain state dots and vortex state dots has been observed from the dependence of vortex nucleation and annihilation fields on interdot separation. A direct consequence of these interactions is the formation of vortex chains as well as dipole chains aligned along the direction of the external field. In addition, short range correlation of chiralities within vortex chains has been observed using magnetic force microscopy imaging and has been attributed to cross-talking between adjacent elements.

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http://dx.doi.org/10.1103/PhysRevLett.88.157203DOI Listing

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