Strain-driven magnetic anisotropy and spin reorientation in epitaxial Co V 2 O 4 spinel oxide thin films

Lamiae El Khabchi; Laurent Schlur; Jérôme Robert; Marc Lenertz; Cédric Leuvrey; Gilles Versini; François Roulland; Gilbert Chahine; Nils Blanc; Daniele Preziosi; Christophe Lefèvre; Nathalie Viart

arXiv · 2603.08187

Strain-driven magnetic anisotropy and spin reorientation in epitaxial Co V 2 O 4 spinel oxide thin films

Lamiae El Khabchi·Laurent Schlur·Jérôme Robert·Marc Lenertz·Cédric Leuvrey·Gilles Versini·François Roulland·Gilbert Chahine·Nils Blanc·Daniele Preziosi·Christophe Lefèvre·Nathalie Viart

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Abstract

CoV___O___ (CVO) stands out among spinel vanadates for its ultra-short V-V distances, placing it at the brink of itinerant electron behaviour-an ideal playground for strain engineering. In this work, we exploit this sensitivity by growing high-quality epitaxial CVO thin films on SrTiO___ (001) and MgO (001), inducing compressive and tensile strain, respectively. Using pulsed laser deposition under ultra-low oxygen pressure, we achieve high crystalline quality and straincontrolled tetragonal distortions: c > a under compression (STO) and c < a under tension (MgO). Resonant elastic X-ray scattering confirms a normal spinel structure, with cobalt occupying tetrahedral sites and vanadium octahedral ones. Both strain types reduce charge transport, driving the system into a highly resistive state. Magnetic measurements reveal strain-driven anisotropy switching: STO films transition from out-of-plane to in-plane easy axis below 90 K, while MgO films flip from in-plane to out-of-plane below 45 K. These results highlight CVO's exceptional responsiveness to lattice strain, unlocking a path to finely tunable electronic and magnetic properties. With its strong spin-lattice coupling and potential in spin Hall magnetoresistance, strained CVO emerges as a compelling platform for next-generation lowpower spintronic devices.

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Lamiae El Khabchi, Laurent Schlur, Jérôme Robert, Marc Lenertz, Cédric Leuvrey, Gilles Versini, François Roulland, Gilbert Chahine, Nils Blanc, Daniele Preziosi, Christophe Lefèvre, Nathalie Viart. 2026-03-09. Strain-driven magnetic anisotropy and spin reorientation in epitaxial Co V 2 O 4 spinel oxide thin films. https://arxiv.org/abs/2603.08187

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