Physical properties of Cd doped CeIrIn₅ under pressure

抄録

We measured the electrical resistivity ρ of CeIr(In_1−xCd_x)₅ under pressure for x = 0.05 and 0.10, which show the onset of superconductivity (SC) at T_sc^onset ~ 0.9 K and antiferromagnetic transition at T_N ~ 3.4 K. For x = 0.05, T_sc^onset increases by applying pressure up to 2.8 GPa and zero resistivity is observed at T_sc^ρ=0 above 2.4 GPa. For x = 0.10, the pressure dependence of T_N shows peak at around 2 GPa and T_N seems to be 0 K toward 3 GPa, where SC phase appears. The maximum value of T_sc^ρ=0 is independent on amount of doped Cd, showing 1.35 K. We analyzed the temperature dependence of the electrical resistivity ρ for x = 0.05 and 0.10 under pressure using the following equation, ρ = ρ₀ + ATⁿ. This analysis revealed that ρ shows the sublinear temperature dependence (n < 1) in the wide temperature region above T_sc^ρ=0, and ρ₀ decreases abruptly in the pressure region where T_sc^ρ=0 indicates a maximum.