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arXiv · 2208.09064

Investigation of role of antisite disorder in the pristine cage compound FeGa$_3$

C. Kaufmann Ribeiro·L. Mello·V. Martelli·D. Cornejo·M. B. Silva Neto·E. Fogh·H. M. Rønnow·J. Larrea Jiménez
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Abstract

The role of controlled disorder in the strong correlated narrow gap semiconductor candidate FeGa$_3$ has been investigated. Polycrystalline samples were synthesized by the combination of arc-melting furnace and successive annealing processes. Deviations of the occupation number of Fe and Ga sites from those expected in the pristine compound were quantified with X-ray analysis. Besides that, electrical transport and magnetization measurements reveal that hierarchy in Fe and Ga site disorder tunes the ground state of FeGa$_3$ from paramagnetic semiconducting to a magnetic metal. These findings are discussed within the framework of Anderson metal-insulator transitions and spin fluctuations.

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C. Kaufmann Ribeiro, L. Mello, V. Martelli, D. Cornejo, M. B. Silva Neto, E. Fogh, H. M. Rønnow, J. Larrea Jiménez. 2022-08-18. Investigation of role of antisite disorder in the pristine cage compound FeGa$_3$. https://arxiv.org/abs/2208.09064

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