TLS Kondo effect in structurally disordered ThAsSe

Abstract Low-temperature electrical-resistivity, ρ ( T ), measurements on single crystals of the structurally disordered ThAsSe reveal an anomalous scattering mechanism, which is apparently derived from two-level systems. For the ThAsSe specimen displaying a resistivity saturation at millikelvin temperatures, a crossover from a logarithmic to a non-Fermi-liquid behavior Δ ρ ∝1− aT 1/2 is observed upon cooling below ≃4 K . A comparison of experimental results with the theoretical ones yields a characteristic energy scale of the order of a few K for ThAsSe.