ScholarWorks@성균관대학교

초록

Chemical substitution in correlated electron systems often produces asymmetric doping effects, where different dopants induce qualitatively distinct changes in electronic or magnetic properties, profoundly influencing phase diagrams and quantum criticality. Here, we investigate the chemical substitution effects of 5% Hg on CeRhIn5 by systematic transport measurements under pressure. In contrast to dilute hole-doped (0.45% Hg) CeRhIn5, which exhibits superconductivity near a Kondo-breakdown type antiferromagnetic (AFM) quantum critical point (QCP), or electron-doped (4.4% Sn) CeRhIn5, which shows superconductivity near a spin-density-wave (SDW) type QCP, the heavily hole-doped (5% Hg) compound shows no superconductivity and evolves through two distinct AFM phases before entering a Fermi-liquid regime, with the AFM QCP likely of SDW type. The contrasting responses to electron and hole substitutions arise from their distinct influences on the local electronic structure. Electron doping induces homogeneous effects, whereas hole doping nucleates localized magnetic droplets that grow with increasing concentration, stabilizing new AFM order and weakening Kondo coupling. These results demonstrate how asymmetric doping reshapes the interplay between magnetism, superconductivity, and quantum criticality, providing mechanistic insights into doping-tuned quantum phase evolution and criticality in heavy-fermion and other correlated electron systems.

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