Effect of flattened surface morphology of anodized aluminum oxide templates on the magnetic properties of nanoporous Co/Pt and Co/Pd thin multilayered films

• For the first time, nanoporous Al2O3 templates with smoothed surface relief characterized by flattened interpore areas were used in the fabrication of Co/Pd and Co/Pt multilayers (MLs) with strong perpendicular magnetic anisotropy (PMA). Alternating gradient magnetometry (AGM) revealed perfectly conserved PMA in the Co/Pd and Co/Pt porous MLs (antidot arrays) with a ratio of remanent magnetization (Mr) to saturation magnetization (MS) of about 0.99, anisotropy fields (Ha) of up to 2.6 kOe, and a small deviation angle of 8° between the easy magnetization axis and the normal to the film surface. The sufficient magnetic hardening of the porous MLs with enhanced coercive field HC of up to ∼1.9 kOe for Co/Pd and ∼1.5 kOe for Co/Pt MLs, as compared to the continuous reference samples (∼1.5–2 times), is associated with the pinning of the magnetic moments on the nanopore edges. Application of the Stoner–Wohlfarth model for fitting the experimental M/MS(H) curves yielded clear evidence of the predominantly coherent rotation mechanism of magnetization reversal in the porous films.

Subject headings

NATURVETENSKAP  -- Fysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences (hsv//eng)

Keyword

Antidots

Co/Pd multilayers

Co/Pt multilayers

Percolated perpendicular media

Perpendicular magnetic anisotropy

Porous anodic aluminum oxide templates

Aluminum

Anisotropy

Anodic oxidation

Curve fitting

Magnetic anisotropy

Magnetic moments

Magnetic multilayers

Magnetism

Magnetization

Magnetization reversal

Multilayers

Oxide films

Oxides

Saturation magnetization

Co/Pt multilayer

Perpendicular media

Cobalt

Antidots

Co/Pd multilayers

Co/Pt multilayers

Percolated perpendicular media

Perpendicular magnetic anisotropy

Porous anodic aluminum oxide templates

Aluminum

Anisotropy

Anodic oxidation

Curve fitting

Magnetic anisotropy

Magnetic moments

Magnetic multilayers

Magnetism

Magnetization

Magnetization reversal

Multilayers

Oxide films

Oxides

Saturation magnetization

Co/Pt multilayer

Perpendicular media

Cobalt

Publication and Content Type

ref (subject category)

art (subject category)