La substitution induced linear temperature dependence of electrical resistivity and Kondo behavior in the alloys, Ce<SUB>2−x</SUB>La<SUB>x</SUB>CoSi<SUB>3</SUB>

Results of electrical resistivity (&#961;), heat-capacity (C) and magnetic susceptibility (&#967;) measurements (above 1.5 K) for the alloys of the type, Ce2&#8722;xLaxCoSi3, are reported. We find that the S-shaped temperature dependence of &#961; for the mixed-valent x=0.0 alloy is not a single-ion property; the most interesting observation is that, for an intermediate concentration, (x=0.25), a linear temperature dependence of &#961; below 30 K is found, an observation of relevance to the current trends in the topic of non-Fermi-liquid behavior. Other observations are: (i) Ce exhibits single-ionic heavy-fermion behavior with moderately enhanced electronic contribution to C; and (ii) the strength of the Kondo interaction, as measured by the Curie-Weiss parameter gets reduced for larger substitutions (x &gt; 0.5) of La for Ce