https://doi.org/10.1007/s100510050575
X-ray spectroscopy of the metal-insulator transition in Yb1-xGdxTe and Yb1-xLaxTe
1
Laboratoire de Chimie Métallurgique des Terres Rares, Centre National de la
Recherche Scientifique,
1 place A. Briand, 92195 Meudon Cedex, France
2
Laboratoire de Physico-Chimie de la Matière Condensée, Université des Sciences
et Techniques du Languedoc,
place Eugène Bataillon, 34095 Montpellier Cedex 5, France
3
Laboratoire des Milieux Désordonnés et Hétérogènes, Université Pierre et Marie
Curie, 4 place Jussieu,
75251 Paris Cedex 05, France
4
Laboratoire de Physique des Solides, Centre National de la Recherche
Scientifique, 1 place A. Briand,
92195 Meudon Cedex, France
Corresponding author: a mauger@aomc.jussieu.fr
Received:
23
March
1998
Accepted:
12
July
1998
Published online: 15 December 1998
We report extended X-ray absorption fine structure (EXAFS) of Yb1-xGdxTe and
Yb1-xLaxTe, two solid solutions which show an insulator-metal transition (IMT)
as a function of x for a high donor concentration . The results are
correlated to transport experiments and X-ray diffraction data, to analyse the IMT in
relation to the structure at both a local and a macroscopic scale. A bimodal
distribution is found for rare earth-Te nearest distances in these compounds
crystallized in the fcc structure. In particular, we find the less rigid Yb–Te bond
can be used as a local probe for the wavefunction of the electrons introduced by La or
Gd donors, hence a new insight on the metal-insulator transitions which are of a
different nature in the two solid solutions.
PACS: 71.30.+h – Metal insulator transitions and other electronic transitions / 61.10.Ht – X-ray absorption spectroscopy: EXAFS, NEXAFS, XANES, etc.
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 1998