TLS Kondo effect in structurally disordered ThAsSe

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 Δρ∝1-aT1/2 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