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Title: Ferromagnetic resonance in low interacting permalloy nanowire arrays

Abstract

Dipolar interactions on magnetic nanowire arrays have been investigated by various techniques. One of the most powerful techniques is the ferromagnetic resonance spectroscopy, because the resonance field depends directly on the anisotropy field strength and its frequency dependence. In order to evaluate the influence of magnetostatic dipolar interactions among ferromagnetic nanowire arrays, several densely packed hexagonal arrays of NiFe nanowires have been prepared by electrochemical deposition filling self-ordered nanopores of alumina membranes with different pore sizes but keeping the same interpore distance. Nanowires’ diameter was changed from 90 to 160 nm, while the lattice parameter was fixed to 300 nm, which was achieved by carefully reducing the pore diameter by means of Atomic Layer Deposition of conformal Al{sub 2}O{sub 3} layers on the nanoporous alumina templates. Field and frequency dependence of ferromagnetic resonance have been studied in order to obtain the dispersion diagram which gives information about anisotropy, damping factor, and gyromagnetic ratio. The relationship between resonance frequency and magnetic field can be explained by the roles played by the shape anisotropy and dipolar interactions among the ferromagnetic nanowires.

Authors:
; ; ;  [1]; ; ;  [2]
  1. Departamento de Física Aplicada, University of Salamanca, E-37071 Salamanca (Spain)
  2. Departamento de Física, Universidad de Oviedo, E-33007 Oviedo (Spain)
Publication Date:
OSTI Identifier:
22594584
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 119; Journal Issue: 14; Other Information: (c) 2016 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ALUMINIUM OXIDES; ANISOTROPY; DAMPING; DIAGRAMS; DISPERSIONS; ELECTROCHEMISTRY; ELECTRODEPOSITION; FERROMAGNETIC RESONANCE; FREQUENCY DEPENDENCE; GYROMAGNETIC RATIO; INTERACTIONS; LATTICE PARAMETERS; LAYERS; MAGNETIC FIELDS; MEMBRANES; NANOWIRES; PERMALLOY; SPECTROSCOPY

Citation Formats

Raposo, V., Zazo, M., Flores, A. G., Iñiguez, J., Garcia, J., Vega, V., and Prida, V. M. Ferromagnetic resonance in low interacting permalloy nanowire arrays. United States: N. p., 2016. Web. doi:10.1063/1.4945762.
Raposo, V., Zazo, M., Flores, A. G., Iñiguez, J., Garcia, J., Vega, V., & Prida, V. M. Ferromagnetic resonance in low interacting permalloy nanowire arrays. United States. doi:10.1063/1.4945762.
Raposo, V., Zazo, M., Flores, A. G., Iñiguez, J., Garcia, J., Vega, V., and Prida, V. M. 2016. "Ferromagnetic resonance in low interacting permalloy nanowire arrays". United States. doi:10.1063/1.4945762.
@article{osti_22594584,
title = {Ferromagnetic resonance in low interacting permalloy nanowire arrays},
author = {Raposo, V. and Zazo, M. and Flores, A. G. and Iñiguez, J. and Garcia, J. and Vega, V. and Prida, V. M.},
abstractNote = {Dipolar interactions on magnetic nanowire arrays have been investigated by various techniques. One of the most powerful techniques is the ferromagnetic resonance spectroscopy, because the resonance field depends directly on the anisotropy field strength and its frequency dependence. In order to evaluate the influence of magnetostatic dipolar interactions among ferromagnetic nanowire arrays, several densely packed hexagonal arrays of NiFe nanowires have been prepared by electrochemical deposition filling self-ordered nanopores of alumina membranes with different pore sizes but keeping the same interpore distance. Nanowires’ diameter was changed from 90 to 160 nm, while the lattice parameter was fixed to 300 nm, which was achieved by carefully reducing the pore diameter by means of Atomic Layer Deposition of conformal Al{sub 2}O{sub 3} layers on the nanoporous alumina templates. Field and frequency dependence of ferromagnetic resonance have been studied in order to obtain the dispersion diagram which gives information about anisotropy, damping factor, and gyromagnetic ratio. The relationship between resonance frequency and magnetic field can be explained by the roles played by the shape anisotropy and dipolar interactions among the ferromagnetic nanowires.},
doi = {10.1063/1.4945762},
journal = {Journal of Applied Physics},
number = 14,
volume = 119,
place = {United States},
year = 2016,
month = 4
}
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