Suppression of Antiferromagnetism by Kondo Effect and Quantum Critical Behavior in CeCoGe_3-xSi_x (0≤ x≤ 3)

Abstract

Several pseudoternary compounds of the CeCoGe_3-xSi_x system were studied by magnetic-susceptibility, electrical-resistivity and specific-heat measurements. Substitution of silicon for germanium generates the normal chemical pressure and enhances the exchange interaction. The antiferromagnetism in CeCoGe₃ is ultimately suppressed around x=1.2 by the enhanced Kondo effect. Non-Fermi liquid-like behavior has been observed around the critical concentration and an intermediate-valence regime with a very high Kondo temperature of the order of 900, K is followed farther on in the silicon rich region.