Magnetic properties of Co nanopillar arrays prepared from alumina templates

Abstract

The preparation of magnetic nanopillars from anodic alumina templates represents a cheap way to obtain extensive ordered arrays, and thus is very appealing for nanotechnology applications. In this paper we report the preparation of arrays of Co nanopillars with 120 nm height and varying diameter. The high anisotropy of Co offers an additional possibility to control their magnetic properties. The magnetic properties of arrays of Co nanopillars are studied both experimentally and by micromagnetic simulations. Experiment and modeling show crucial changes of hysteresis loops when the diameter is increased. Magnetic data are interpreted considering the change of crystalline structure as well as the influence of geometry. The micromagnetic simulations explain the measured magnetic properties by the role of magnetocrystalline anisotropy and the combined influence of the shape anisotropy and the interactions. They also show the change in the reversal mode with the increased diameter from vortex propagation to curling when the field is applied parallel to the nanopillar axis, and from coherent rotation to curling when it is applied perpendicular.

Magnetotransport Measurements of Domain Wall Propagation in Individual Multisegmented Cylindrical Nanowires

“…Anodic aluminum oxide (AAO) is commonly used as a template as it exhibits a highly ordered hexagonal pore structure with controllable pore diameter and inter-pore distances [5]. In this paper, AAO templates are prepared inhouse by a two-step anodization process of highly pure (99.9995%) Al discs.…”

Template Synthesis and Magnetic Characterization of Feni Nanotubes

“…The method consists in that pores in the templates are filled in with material. Ion-track membranes [16] or matrices of anodized aluminum oxide [17] are usually used as templates. Both types of templates have parallel pores and allow synthesizing NTs and NWs from a diameter of several tens of nanometers.…”

“…The most widely used method of metallic nanostructures synthesis is the electrochemical deposition, which allows to efficiently manage the physical and chemical properties of the nanostructures with high degree of process control [8,17,23].…”

Структура И Физические Свойства Железных Нанотрубок, Полученных Методом Темплатного Синтеза

“…Он наиболее технологичный, так как поз-воляет контролировать морфологию, структуру, состав и соответственно магнитные свойства наноструктур за счет изменения ряда внешних параметров: температуры, состава и кислотности электролита, напряжения на элек-тродах и времени осаждения [6,[9][10][11]. В настоящее вре-мя довольно хорошо отработаны механизмы получения магнитных нанопроволок с использованием подложек из Si [12], Al 2 O 3 [13] и SiO 2 [14].…”