Synthesis and Transfer of Freestanding Strain-Engineered Vertically Aligned Nanocomposite Thin Films

Carlos Rodríguez Cortéz; Moussa Mebarki; Bruno Berini; Dominique Demaille; Vincent Polewczyk; Yunlin Zheng; Pal Bhuyan; Boris Vodungbo; Emmanuelle Jal; Horia Popescu; Nicolas Jaouen; Yves Dumont; Marcel Hennes; Franck Vidal

arXiv · 2603.15772

Synthesis and Transfer of Freestanding Strain-Engineered Vertically Aligned Nanocomposite Thin Films

Carlos Rodríguez Cortéz·Moussa Mebarki·Bruno Berini·Dominique Demaille·Vincent Polewczyk·Yunlin Zheng·Pal Bhuyan·Boris Vodungbo·Emmanuelle Jal·Horia Popescu·Nicolas Jaouen·Yves Dumont·Marcel Hennes·Franck Vidal

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Abstract

The recent development of freestanding oxide thin films opens up exciting opportunities for the design of novel heterostructures with enhanced functionalities. Here, we explore the fabrication of membranes consisting of dense arrays of ultrathin CoxNi1-x nanowires epitaxially embedded in a SrTiO3 matrix. Through combined x-ray absorption spectroscopy, x-ray resonant magnetic scattering, x-ray diffraction and magnetooptical experiments, we show how a SrVO3-mediated lift-off process can be used to create and transfer these membranes while simultaneously preserving the structural and chemical integrity of the self-assembled, metallic CoxNi1-x nanopillars. With this approach, the large axial deformation of the embedded nanostructures is kept intact and, as a direct consequence, the magnetic properties of the nano-composite thin films remain largely unaltered after substrate removal. Our findings thus highlight a novel route for the synthesis of freestanding, strain-engineered vertically aligned heterostructures and pave the way for their future integration into spintronic and optomagnetic devices.

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Carlos Rodríguez Cortéz, Moussa Mebarki, Bruno Berini, Dominique Demaille, Vincent Polewczyk, Yunlin Zheng, Pal Bhuyan, Boris Vodungbo, Emmanuelle Jal, Horia Popescu, Nicolas Jaouen, Yves Dumont, Marcel Hennes, Franck Vidal. 2026-03-16. Synthesis and Transfer of Freestanding Strain-Engineered Vertically Aligned Nanocomposite Thin Films. https://arxiv.org/abs/2603.15772

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