Magnetic Configurations in Modulated Cylindrical Nanowires
Cristina Bran, Jose Angel Fernandez-Roldan, Rafael P. del Real, Agustina Asenjo, Oksana Chubykalo-Fesenko and Manuel Vazquez
Nanomaterials 2021, 11, 600
DOI: doi.org/10.3390/nano11030600
Cylindrical magnetic nanowires show great potential for 3D applications such as magnetic recording, shift registers, and logic gates, as well as in sensing architectures or biomedicine. Their cylindrical geometry leads to interesting properties of the local domain structure, leading to multifunctional responses to magnetic fields and electric currents, mechanical stresses, or thermal gradients. This review article summarizes the work carried out in our group on the fabrication and magnetic characterization of cylindrical magnetic nanowires with modulated geometry and anisotropy. The nanowires are prepared by electrochemical methods with precise control over geometry, morphology, and composition. Different routes to control the magnetization configuration and its dynamics through the geometry and magnetocrystalline anisotropy are presented. The diameter modulations change the typical single domain state present in cubic nanowires, providing the possibility to confine or pin circular domains or domain walls in each segment. The control and stabilization of domains and domain walls in cylindrical wires has been achieved in multisegmented structures by alternating magnetic segments of different magnetic properties or with non-magnetic layers.
This article reviews the most significant investigations carried out by the GNMP group on cylindrical magnetic nanowires with modulated geometry and anisotropy. Such modulations promote the occurrence of stable magneto-chiral structures and provide further information for the design of cylindrical nanowires for multiple applications.