Andreev conductance of a domain wall

At low temperatures the transport through a superconductor-ferromagnet (SF) tunnel interface is due to the tunneling of electrons in pairs. The exchange field of a single domain ferromagnet aligns electron spins and suppresses the two-electron tunneling. The presence of the domain walls at the SF interface strongly enhances the subgap current. The Andreev conductance is proved to be proportional to the total length of domain walls at the SF interface when the ferromagnet is fully polarized.