High Field Magnetotransport in CeRh1-xIrxIn5 Heavy Electron Alloys

The interplay of magnetism and superconductivity has been a recurring theme in heavy fermion compounds. Recently, alloys of CeRhIn₅ (antiferromagnet at 3.8 K) and CeIrIn₅ (superconductor at 0.4 K) have been grown, i.e. CeRh_1-xIr_xIn₅. For x = 0.5, specific heat and magnetic susceptibility measurements indicate at ~3.6 K an antiferromagnetic transition occurs. Decreasing temperature still further, a superconducting transition is observed at 0.8 K. Thus this alloy series offers the possibility of exploring the coexistence of superconductivity and magnetism in a Ce-based heavy fermion system. We have initiated a magnetotransport study from 1.4 to 300 K with applied fields to 18 T, to probe the behavior of these systems at temperatures above the possible coexistence region. In this paper we will focus on comparing the high field magnetotransport properties of CeRh_0.9Ir_0.1In₅ to the end compounds CeRhIn₅ and CeIrIn₅.