We present point-contact measurements of the antiferromagnetic heavy-fermion superconductor ${\mathrm{URu}}_2$${\mathrm{Si}}_2$. Our data in the superconducting state agree remarkably well with the theory of Blonder, Tinkham, and Klapwijk (BTK), and are consistent with a gap with d-wave symmetry. In the normal state a ‘‘gap’’ in the conductance develops as the temperature is lowered below the Néel temperature. The persistence of this gap into the superconducting state supports the view that magnetically correlated electrons participate in the superconductivity.

• Received 5 February 1992

DOI:https://doi.org/10.1103/PhysRevB.46.5826