Electrical resistivity of the Kondo systems (Ce 1− xLa x)TSi 3[formula omitted

Abstract

The electrical resistivities of the pseudo-ternary alloys (Ce 1− x La x )TSi 3 ( T= Rh, Ir; 0≤x≤1) are reported. The 4f-derived part of their resistivities, ρ 4f, is found by subtracting the temperature-dependent part of the resistivity of LaTSi 3. A maximum, characteristic of dense Kondo systems, is obtained in ρ 4f at a temperature T max =105 K for CeRhSi 3 and at 130 K for CeIrSi 3. T max decreases for both compounds with increased La concentration, x. X-ray powder diffraction was used to measure the increase in tetragonal unit cell volume V for the (Ce 1− x La x )TSi 3 alloys with increase in x. The compressible Kondo model is applied to describe our results of T max( x) in terms of the on-site Kondo exchange interaction J and the electronic density of states N( E F) at the Fermi level. The experimental results yield | JN( E F)| x=0 =0.072±0.016 for CeRhSi 3 and 0.070±0.001 for CeIrSi 3.