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arXiv · 2302.13845

Ferromagnetism and Metal-Insulator transition in F-doped LaMnO3

Ekta Yadav·Pramod Ghising·K. P. Rajeev·Z. Hossain
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Abstract

We present our studies on polycrystalline samples of fluorine doped LaMnO3 (LaMnO3-yFy). LaMnO2.5F0.5 exhibits remarkable magnetic and electrical properties. It shows ferromagnetic and metallic behavior with a high Curie temperature of ~ 239 K and a high magnetoresistance of -64. This drastic change in magnetic properties in comparison to pure LaMnO3 is ascribed to the presence of mixed-valence Mn ions driven by the F-doping at the O-sites, which enables double exchange (DE) in LMOF. Furthermore, the resistivity data exhibits two resistivity peaks at 239 K and 213 K, respectively. Our results point towards the possibility of multiple double exchange hopping paths of two distinct resistances existing simultaneously in the sample below 213 K.

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Ekta Yadav, Pramod Ghising, K. P. Rajeev, Z. Hossain. 2023-02-27. Ferromagnetism and Metal-Insulator transition in F-doped LaMnO3. https://doi.org/10.1103/physrevb.107.214446

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