Magnetotransport properties governed by antiferromagnetic fluctuations in the heavy-fermion superconductor CeIrIn5

In quasi-two-dimensional Ce(Ir,Rh)In-5 system, it has been suggested that the phase diagram contains two distinct domes with different heavy-fermion superconducting states. Here, we report the systematic pressure dependence of the electron transport properties in the normal state of CeRh0.2Ir0.8In5 and CeIrIn5, which locates in first and second superconducting domes, respectively. We observed non-Fermi liquid behavior at low temperatures in both compounds, including nonquadratic T dependence of the resistivity, large enhancement of the Hall coefficient, and the violation of the Kohler rule in the magnetoresistance. We show that the cotangent of the Hall angle cot Theta(H) varies as T-2, and the magnetoresistance is quite scaled well by the Hall angle as Delta rho(xx)/rho(xx)proportional to tan(2) Theta(H). The observed transport anomalies are common features of CeMIn5 (M=Co, Rh, and Ir) and high-T-c cuprates, which suggest that the anomalous transport properties observed in CeIrIn5 are mainly governed by the antiferromagnetic spin fluctuations not by the Ce-valence fluctuations, which have been proposed to be the possible origin for the second superconducting dome.