Tunneling anomalies and the coexistence of ferromagnetism and superconductivity in ErRh4B4 films

Single-particle tunneling measurements have been used to study the paramagnetic, superconducting, and ferromagnetic phases of polycrystalline films of the reentrant superconductor ErRh4B4. Anomalous features of the tunneling conductance in the ferromagnetic phase which persist into the superconducting state have been observed. These features seem intimately connected with the onset of ferromagnetism in the region of coexistence of ferromagnetism and superconductivity just above Tc2.