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arXiv · 2210.01039

The effect of vanadium substitution on the structural and magnetic properties of (Fe$_{1-x}$V$_{x}$)$_{3}$Ga$_{4}$

Brandon Wilfong·Vaibhav Sharma·Omar Bishop·Adrian Fedorko·Don Heiman·Radhika Barua·Michelle E. Jamer
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Abstract

Fe$_{3}$Ga$_{4}$ displays a complex magnetic phase diagram that is sensitive and tunable with both electronic and crystallographic structure changes. In order to explore this tunability, vanadium-doped (Fe$_{1-x}$V$_{x}$)$_{3}$Ga$_{4}$ has been synthesized and characterized. High-resolution synchrotron X-ray diffraction and Rietveld refinement show that samples up to 20\% V-doping remain isostructural to Fe$_{3}$Ga$_{4}$ and display a linear increase in unit cell volume as doping is increased. Magnetic measurements reveal a suppression of the antiferromagnetic helical spin-density wave (SDW) with V-doping, revealed by changes in both the low-temperature ferromagnetic-antiferromagentic (FM-AFM) transition (T$_{1}$) and high-temperature AFM-FM transition (T$_{2}$). At 7.5\% V-doping, the metamagnetic behavior of the helical AFM SDW phase is no longer observed. These results offer an avenue to effective tuning of the magnetic order in Fe$_{3}$Ga$_{4}$ for devices, as well as increased understanding of the magnetism in this system.

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Brandon Wilfong, Vaibhav Sharma, Omar Bishop, Adrian Fedorko, Don Heiman, Radhika Barua, Michelle E. Jamer. 2022-10-03. The effect of vanadium substitution on the structural and magnetic properties of (Fe$_{1-x}$V$_{x}$)$_{3}$Ga$_{4}$. https://doi.org/10.1016/j.jmmm.2022.169964

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