A Magnetic and Magneto-Optical Investigation of Co-Pt Alloy Nanowire Arrays

Abstract

We have investigated the magneto-optical properties of highly ordered Co-Pt alloy nanowire arrays embedded in anodic aluminum oxide templates. The magnetic field-dependent Stokes parameters, Faraday rotation angle and ellipticity were investigated by an in-house magneto-optical measurement system. The extracted hysteresis loops are broadly consistent with magnetic hysteresis loops obtained from the vibrating sample magnetometer. The maximum Faraday rotation angle and ellipticity of these samples were examined as a function of nanowire composition. With an increase of platinum content from 9 at.% to 86 at.% in the as-deposited nanowire arrays, the maximum Faraday rotation angle per length decreases linearly from 1.39 x 10(3) degrees/cm to 1.58 x 10(2) degrees/cm. The maximum ellipticity shows a similar behavior with the composition. These linear relationships suggest a dilution model for the magnetic moment in the alloy nanowires. Our results indicate that magneto-optical measurements comprise an effective and sensitive method for monitoring the behavior of AAO-based magnetic nanowire arrays.

Enhanced magneto-optical effects in composite coaxial nanowires embedded with Ag nanoparticles

“…Therefore, researchers have focused on improving the FM performance through structural optimization 5 9 10 11 12 13 . Nanowire (NW) arrays are preferred and widely used for this optimization because of their low reflectance and cavity effect 14 15 16 . Additionally, nanostructures decorated with noble metals have been extensively introduced to enhance the Faraday effect through surface plasmon polariton (SPP) or localized surface plasmon resonance (LSPR) effects 5 11 12 17 18 19 20 21 22 23 24 25 .…”