Coexistence of magnetism and superconductivity inCeRh1−xIrxIn5

We report a thermodynamic and transport study of the phase diagram of ${\mathrm{CeRh}}_{1-x}{\mathrm{Ir}}_x{\mathrm{In}}_5.$ Bulk superconductivity is observed over a broad range of doping, $0.3<x<~1,$ including a substantial range $\mathrm{}(0.3<x<\mathrm{}0.6\mathrm{})\mathrm{}$ over which it coexists with magnetic order (which is observed for $0<~x<\mathrm{}0.6).\mathrm{}$ The anomalous transition to zero resistance that is observed in ${\mathrm{CeIrIn}}_5$ is robust against Rh substitution: the bulk $T_c$ in ${\mathrm{CeRh}}_{0.5}{\mathrm{Ir}}_{0.5}{\mathrm{In}}_5$ is more than double that of ${\mathrm{CeIrIn}}_5,$ whereas the zero-resistance transition temperature is relatively unchanged for $0.5<x<\mathrm{}1.\mathrm{}$