Magnetic transition in the heavy fermion compound URu2−xRexSi2

Abstract On partially substituting Ru atoms by Re in the well-known antiferromagnetic superconductor URu 2 Si 2 an itinerant ferromagnetic state progressively develops. Simultaneously the partial gap at the Fermi surface, associated with the formation of a spin density wave ground state in the undoped material, is closed. We present point-contact measurements of the system URu 2− x Re x Si 2 with x in the range 0–0.8. A maximum around zero bias in the differential resistance of URu 2 Si 2 is assumed to represent the spin density wave gap on the Fermi surface. The influence of the Re substitution on the maximum as well as the temperature and magnetic field dependence of the zero bias structure are presented.