Magnetic Properties of Ni-Fe Nanowire Arrays: Effect of Template Material and Deposition Conditions

TL;DR

This study investigates how different template materials, magnetic field application during deposition, and wire length affect the magnetic properties of Ni-Fe nanowire arrays, revealing significant anisotropy and property variations.

Contribution

It provides new insights into how template material and deposition conditions influence the magnetic anisotropy and coercivity of Ni-Fe nanowires.

Findings

Magnetic field during deposition enhances perpendicular anisotropy.

Polycarbonate templates show increased coercivity with magnetic field.

Longer wires exhibit decreased coercivity and squareness ratio.

Abstract

The objective of this work is to study the magnetic properties of arrays of Ni-Fe nanowires electrodeposited in different template materials such as porous silicon, polycarbonate and alumina. Magnetic properties were studied as a function of template material, applied magnetic field (parallel and perpendicular) during deposition, wire length, as well as magnetic field orientation during measurement. The results show that application of magnetic field during deposition strongly influences the c-axis preferred orientation growth of Ni-Fe nanowires. The samples with magnetic field perpendicular to template plane during deposition exhibits strong perpendicular anisotropy with greatly enhanced coercivity and squareness ratio, particularly in Ni-Fe nanowires deposited in polycarbonate templates. In case of polycarbonate template, as magnetic field during deposition increases, both coercivity and squareness ratio also increase. The wire length dependence was also measured for polycarbonate templates. As wire length increases, coercivity and squareness ratio decrease, but saturation field increases. Such magnetic behavior (dependence on template material, magnetic field, wire length) can be qualitatively explained by preferential growth phenomena, dipolar interactio