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arXiv · 0905.2684

Local-moment ferromagnetism and unusual magnetic domains in Fe$_{1/4}$TaS$_{2}$ crystals

M. D. Vannette·S. Yeninas·E. Morosan·R. J. Cava·R. Prozorov
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Abstract

Single crystals of Fe$_{1/4}$TaS$_{2}$ have been studied by using magneto-optical (MO) imaging and radio-frequency (rf) magnetic susceptibility, $χ$. Real time MO images reveal unusual, slow dynamics of dendritic domain formation, the details of which are strongly dependent upon magnetic and thermal history. Measurements of $χ(T)$ show well-defined, local moment ferromagnetic transition at $T\approx 155$ K as well as thermal hysteresis for 50 K$<T<$60 K. This temperature range corresponds to the domain formation temperature as determined by MO. Together these observations provide strong evidence for local moment ferromagnetism in Fe$_{1/4}$TaS$_{2}$ crystals with large, temperature dependent magnetic anisotropy.

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M. D. Vannette, S. Yeninas, E. Morosan, R. J. Cava, R. Prozorov. 2009-05-16. Local-moment ferromagnetism and unusual magnetic domains in Fe$_{1/4}$TaS$_{2}$ crystals. https://doi.org/10.1103/physrevb.80.024421

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