Magnetic and structural properties of fcc/hcp bi-crystalline multilayer Co nanowire arrays prepared by controlled electroplating

We report on the structural and magnetic properties of crystalline bi-phase Co nanowires, electrodeposited into the pores of anodized alumina membranes, as a function of their length. Co nanowires present two different coexistent crystalline structures (fcc and hcp) that can be controlled by the tim...

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Bibliographic Details
Authors: Pirota, K.R., Béron, F., Zanchet, D., Rocha, T.C.R., Navas, David, Torrejón, J., Vázquez Villalabeitia, Manuel, Knobel, M.
Format: article
Status:Versión aceptada para publicación
Publication Date:2011
Country:España
Institution:Consejo Superior de Investigaciones Científicas (CSIC)
Repository:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/377713
Online Access:http://hdl.handle.net/10261/377713
https://www.scopus.com/inward/record.uri?eid=2-s2.0-79955709830&doi=10.1063%2f1.3553865&partnerID=40&md5=fdae1e492fd90aa278105433d266d5d2
Access Level:Open access
Keyword:Magnetic anisotropy
Magnetic fields
Crystal structure
Crystalline solids
Electrodeposition
Magnetic hysteresis
Magnetic materials
Thin film deposition
X-ray diffraction
Nanowires
Description
Summary:We report on the structural and magnetic properties of crystalline bi-phase Co nanowires, electrodeposited into the pores of anodized alumina membranes, as a function of their length. Co nanowires present two different coexistent crystalline structures (fcc and hcp) that can be controlled by the time of pulsed electrodeposition. The fcc crystalline phase grows at the early stage and is present at the bottom of all the nanowires, strongly influencing their magnetic behavior. Both structural and magnetic characterizations indicate that the length of the fcc phase is constant at around 260-270 nm. X-ray diffraction measurements revealed a strong preferential orientation (texture) in the (1 0-1 0) direction for the hcp phase, which increases the nanowire length as well as crystalline grain size, degree of orientation, and volume fraction of oriented material. The first-order reversal curve (FORC) method was used to infer both qualitatively and quantitatively the complex magnetization reversal of the nanowires. Under the application of a magnetic field parallel to the wires, the magnetization reversal of each region is clearly distinguishable; the fcc phase creates a high coercive contribution without an interaction field, while the hcp phase presents a smaller coercivity and undergoes a strong antiparallel interaction field from neighboring wires. © 2011 American Institute of Physics.