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arXiv · 2504.00788

Synthesis of Cobalt Grown from Co-S Eutectic in High Magnetic Fields

Steven Flynn·Caeli L. Benyacko·Matúš Mihalik·Jared Lee·Fuyan Ma·Michael E. Bates·Shubham Sinha·Khalil A. Abboud·Marian Mihalik·Mark W. Meisel·James J. Hamlin
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Abstract

Samples of Co were grown directly in the ferromagnetic state under equilibrium conditions using a cobalt sulfide flux. Magnetic fields up to 9 T were applied during growth, and isolated Co products exhibit progressively elongated morphologies, from cubes to rectangular rods to needle-like tendrils with poorly-defined facets. The degree of elongation of the major axis was found to correlate with magnetic field direction, strength, and gradient. Two-dimensional X-ray diffraction data indicate some level of polycrystalline-like samples, and quantitative analyses (Le Bail and Rietveld) of the one-dimensional data confirm the presence of hcp and fcc phases. The magnetic responses indicate a partial alignment of the magnetic easy-axis of the hcp phase along the magnetic field present during growth.

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Steven Flynn, Caeli L. Benyacko, Matúš Mihalik, Jared Lee, Fuyan Ma, Michael E. Bates, Shubham Sinha, Khalil A. Abboud, Marian Mihalik, Mark W. Meisel, James J. Hamlin. 2025-04-01. Synthesis of Cobalt Grown from Co-S Eutectic in High Magnetic Fields. https://doi.org/10.1103/9bb3-4pby

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