Eur. Phys. J. B (2013) 86: 134
https://doi.org/10.1140/epjb/e2013-30935-4

Regular Article

Transverse magnetization in Cu/Ni/Cu epitaxial nanorings^*

¹ Instituto de Ciencia de Materiales de Aragón, Consejo Superior de Investigaciones Científicas, 50009 Zaragoza, Spain
² Laboratorio de Microscopías Avanzadas, Instituto de Nanociencia de Aragón, Universidad de Zaragoza, 50018 Zaragoza, Spain
³ Departamento de Física de la Materia Condensada, Universidad de Zaragoza, 50009 Zaragoza, Spain
⁴ Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge MA 02139-4307, USA

^a e-mail: ciria@unizar.es

Received: 12 October 2012
Received in final form: 10 January 2013
Published online: 8 April 2013

Abstract

The micromagnetic structure in epitaxial (001)-oriented Cu/Ni(14 nm)/Cu rings fabricated by electron beam and focused ion beam lithographies with external diameter of 3 μm and linewidths between 100 and 500 nm is presented. We found that a state with radial orientation of the magnetization prevails at remanence. The evaluation of the magnetoelastic, magnetocrystalline and magnetostatic energies shows that a value as low as 1.5 × 10^-3 for the anisotropic relaxation of the in-plane strain components is enough to induce an effective radial easy magnetization direction.