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First order valence transition in YbInCu_4 in the (B,T) - plane

M. O. Dzero·L. P. Gor'kov·A. K. Zvezdin
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Abstract

The puzzling properties of the first order phase transition in YbInCu$_4$ and its alloys in the wide range of magnetic fields and temperatures are perfectly described in terms of a simple entropy transition for free Yb ions. In particular, it turns out that the transition line in the $(B,T)$-plane is very close to the elliptic shape, as it has been observed experimentally. Similar calculations are done, and the experiments are proposed for the $(γ{-}α)$ phase transition in Ce in Megagauss fields. We speculate, that in case of YbInCu$_4$ the first order transition is a Mott transition between a higher temperature phase in which localized moments are stabilized by the entropy terms in the free energy, and a band-like non-magnetic ground state of the $f$-electrons.

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M. O. Dzero, L. P. Gor'kov, A. K. Zvezdin. 2000-12-11. First order valence transition in YbInCu_4 in the (B,T) - plane. https://doi.org/10.1088/0953-8984%2F12%2F47%2F102

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