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arXiv · 2310.17045

Phase Change Induced Magnetic Switching through Metal-insulator Transition in VO2/TbFeCo Films

Chung T. Ma·Salinporn Kittiwatnakul·Apiprach Sittipongpittaya·Yuhan Wang·Md Golam Morshed·Avik W. Ghosh·S. Joseph Poon
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Abstract

The ability to manipulate spins in magnetic materials is essential in designing spintronics devices. One method for magnetic switching is through strain. In VO2 on TiO2 thin films, while VO2 remains rutile across the metal-insulator transition, the in-plane lattice area expands going from low temperature insulating phase to high temperature conducting phase. In a VO2/TbFeCo bilayer, the expansion of the VO2 lattice area exerts tension on the amorphous TbFeCo layer. Through the strain effect, magnetic properties, including the magnetic anisotropy and magnetization, of TbFeCo can be changed. In this work, the changes in magnetic properties of TbFeCo on VO2/TiO2(011) are demonstrated using anomalous Hall effect measurements. Across the metal-insulator transition, TbFeCo loses perpendicular magnetic anisotropy, and the magnetization in TbFeCo turns from out-of-plane to in-plane. Using atomistic simulations, we confirm these tunable magnetic properties originating from the metal-insulator transition of VO2. This study provides the groundwork for controlling magnetic properties through a phase transition.

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Chung T. Ma, Salinporn Kittiwatnakul, Apiprach Sittipongpittaya, Yuhan Wang, Md Golam Morshed, Avik W. Ghosh, S. Joseph Poon. 2023-10-25. Phase Change Induced Magnetic Switching through Metal-insulator Transition in VO2/TbFeCo Films. https://arxiv.org/abs/2310.17045

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