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arXiv · 2404.03207

Competitive coexistence of ferromagnetism and metal--insulator transition of VO$_2$ nanoparticles

Tsuyoshi Hatano·Akihiro Fukawa·Hiroki Yamamoto·Keiichirou Akiba·Kouichi Takase
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Abstract

We investigated the magnetic and electric properties of nanometer-sized vanadium dioxide (VO$_2$) particles. VO$_2$ nanoparticles were formed by milling VO$_2$ powder. We measured the magnetic field dependence of the magnetization of the VO$_2$ powder and nanoparticles. The VO$_2$ powder did not exhibit ferromagnetism, whereas the VO$_2$ nanoparticles exhibited ferromagnetism. In addition, we fabricated samples by bridging between electrodes with the VO$_2$ nanoparticles, and the temperature dependence of their resistance was measured. Metal-insulator transitions (MITs) were observed, and the temperature range where the MIT occurred was wider than that in a typical bulk VO$_2$. The VO$_2$ nanoparticles exhibited these properties of ferromagnetism and MIT possibly because of the surface and size effects of the VO$_2$ nanoparticles. These results indicate the first observation of the competitive coexistence of ferromagnetism and MIT of VO$_2$ nanoparticles.

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Tsuyoshi Hatano, Akihiro Fukawa, Hiroki Yamamoto, Keiichirou Akiba, Kouichi Takase. 2024-04-04. Competitive coexistence of ferromagnetism and metal--insulator transition of VO$_2$ nanoparticles. https://doi.org/10.35848/1347-4065%2Fad2d04

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