Incoherent Kondo Behaviors in Amorphous Ce_xCu_1−x Alloys

Abstract

Amorphous Ce_1−xCu_x alloys (x=0.09–0.48) have been produced by sputter-deposition. The low-temperature specific heat shows a remarkable enhancement of electronic specific heat coefficient. The magnetic susceptibility can be fitted to a Curie-Weiss law with the effective Bohr magneton number of about 2.5 for T>50 K and 2 for T=10–20 K. The electrical resistivity is dominated by the disorder scattering and shows a weak Kondo-type anomaly at low temperatures. These results indicate that the effective electron mass is very heavy even in the random alloy system, where a long-range magnetic order and formation of degenerated Fermi liquid state are suppressed.