Interplay of atomic randomness and Kondo effect in disordered metallic conductor La₂NiSi₃

A polycrystalline sample of La₂NiSi₃ was investigated by means of heat capacity, magnetic susceptibility, magnetization, electrical resistivity and magnetoresistivity measurements. The compound was basically characterized as a Pauli paramagnet with metallic-like electrical conductivity, notably reduced in magnitude and weakly temperature dependent, as is usually observed for atomically disordered systems. Furthermore, the experimental data revealed the presence of a small amount of paramagnetic impurities. As a result, the low-temperature electrical resistivity in La₂NiSi₃ was found to be governed by both quantum corrections due to electron-electron interactions ( contribution) and spin-flip Kondo scattering ( contribution). The presence of paramagnetic impurities led to an increase in s-electron spin splitting due to the s-d interactions, manifested by a B ^1/2 dependence of the magnetoresistivity, anomalously observed in the present study for thermal energy being larger than the Zeeman splitting energy .