Kondo temperature and Heavy Fermion behavior in Yb1−xYxCuAl series of alloys

Abstract

We report, in the present article, a detailed study of the chemical substitution effects on the magnetic, electronic transport and thermal properties of the intermediate valence system YbCuAl (Yb 1-xYxCuAl series of alloys). A more complete characterization of this series of alloys is provided including the analysis of the thermal and electronic transport properties. It is worth noticing, that less attention has been paid to experimental evidences of the ?negative pressure? effects, within right side of the Doniach diagram, when the systems move away from the QCP. Thus, it is worthwhile to explore the region of higher hybridization states, when some theoretical works point even, to the existence of anomalous Kondo behaviours. The results of this study are explained by the increase of the hybridization as consequence of the negative pressure effects, obtained by the chemical substitution of Yb by Y, thus leading to the increase of TK, in agreement with the Doniach diagram. We think that the subject of this study will be of great interest for both, the readers interested in the properties of Strongly Correlated Electron materials, and those others who work on the also vast field of Rare-Earth intermetallics