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Itinerant Ferromagnetism for Mixed Valence Systems

C. D. Batista·J. Bonča·J. E. Gubernatis
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Abstract

We introduce a novel mechanism for the unusual itinerant ferromagnetism found in mixed valence systems like Ce(Rh$_{1-x}$Ru$_x$)$_3$B$_2$, La$_x$Ce$_{1-x}$Rh$_3$B$_2$, US, USe, and UTe. With it we can provide an explanation for the long-unexplained large value of $T_c$ ($\sim$ 100$^\circ$K) value and the maximum in the magnetization below $T_c$ found experimentally. We also show that this novel itinerent ferromagnetism can be continuously connected with the localized case for which the energy scale is much smaller ($J_{RKKY} \sim$ 1$^\circ$K).

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C. D. Batista, J. Bonča, J. E. Gubernatis. 2001-04-19. Itinerant Ferromagnetism for Mixed Valence Systems. https://arxiv.org/abs/cond-mat/0104351

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