Magnetic and transport properties of PrRhSi₃

We have investigated the magnetic and transport properties of a noncentrosymmetric compound PrRhSi₃ by dc magnetic susceptibility χ(T), isothermal magnetization M(H), thermoremanent magnetization M(t), specific heat C_p(T), electrical resistivity ρ(T,H) and muon spin relaxation (μSR) measurements. At low fields χ(T) shows two anomalies near 15 and 7 K with an irreversibility between ZFC and FC data below 15 K. In contrast, no anomaly is observed in C_p(T) or ρ(T) data. M(H) data at 2 K exhibit very sharp increase below 0.5 T and a weak hysteresis. M(t) exhibits very slow relaxation, typical for a spin-glass system. Even though the absence of any anomaly in C_p(T) is consistent with the spin-glass type behavior, there is no obvious origin of spin-glass behavior in this structurally well ordered compound. The crystal electric field (CEF) analysis of C_p(T) data indicates a CEF-split singlet ground state lying below a doublet at 81(1) K and a quasi-triplet at 152(2) K. The ρ(T) data indicate a metallic behavior, and ρ(H) exhibits a very high positive magnetoresistance, as high as ∼300% in 9 T at 2 K. No long range magnetic order or spin-glass behavior was detected in a μSR experiment down to 1.2 K.