Point-contact spectroscopy of competing/coexisting orders in Cd-doped CeCoIn5

Abstract

Differential conductance spectra are taken from metallic point-contact junctions on Cd-doped CeCoIn5. For (100) junctions with nominal 10% doping, we observe signatures for subsequent antiferromagnetic and superconducting transitions in qualitative agreement with bulk measurements. In the superconducting state, two conductance channels compete, both with enhanced subgap conductance, one due to superconductivity and the other antiferromagnetism. The conductance data exhibit variances for different doping levels and crystallographic orientations and junction to junction. This issue will be addressed further in terms of surface inhomogeneity or intrinsic nonuniform phase formation. © 2009 IOP Publishing Ltd