We set up a simple transfer matrix formalism to study the existence of bound
states at interfaces and in junctions between antiferromagnets and d-wave
superconductors. The well-studied zero energy mode at the {110} interface
between an insulator and a d-wave superconductor is spin split when the
insulator is an antiferromagnet. This has as a consequence that any competing
interface induced superconducting order parameter that breaks the time reversal
symmetry needs to exceed a critical value before a charge current is induced
along the interface.Comment: 4 pages, 3 figure