Growth-Induced In-Plane Uniaxial Anisotropy in V$_{2}$O$_{3}$/Ni Films

TL;DR

This study demonstrates strain-induced, temperature-dependent uniaxial magnetic anisotropy in V₂O₃/Ni films, driven by interfacial strain and microstructure, with implications for tunable magnetic devices.

Contribution

It reveals the origin of uniaxial anisotropy in V₂O₃/Ni films due to strain and microstructure, and shows how it can be tuned with temperature for device applications.

Findings

Uniaxial anisotropy aligned with microstructure rips.

Temperature enhances the anisotropy effect.

Domain wall pinning varies with orientation and temperature.

Abstract

We report on a strain-induced and temperature dependent uniaxial anisotropy in V$_{2}$O$_{3}$/Ni hybrid thin films, manifested through the interfacial strain and sample microstructure, and its consequences on the angular dependent magnetization reversal. X-ray diffraction and reciprocal space maps identify the in-plane crystalline axes of the V$_{2}$O$_{3}$; atomic force and scanning electron microscopy reveal oriented rips in the film microstructure. Quasi-static magnetometry and dynamic ferromagnetic resonance measurements identify a uniaxial magnetic easy axis along the rips. Comparison with films grown on sapphire without rips shows a combined contribution from strain and microstructure in the V$_{2}$O$_{3}$/Ni films. Magnetization reversal characteristics captured by angular-dependent first order reversal curve measurements indicate a strong domain wall pinning along the direction orthogonal to the rips, inducing an angular-dependent change in the reversal mechanism. The resultant anisotropy is tunable with temperature and is most pronounced at room temperature, which is beneficial for potential device applications.