MAGNETIC SCATTERING EFFECTS ON QUANTUM TRANSPORT IN A NORMAL-METAL-SUPERCONDUCTOR JUNCTION

Within a scattering formalism, the magnetic scattering effects on the transport properties of a normal metal attached to a d-wave as well as an s-wave superconductor have been studied by inserting (i) a Kondo-l ike magnetic barrier and (ii) a ferromagnetic scattering layer into th e normal conducting region. It is shown that, in contrary to our intui tion, the Kondo-like magnetic scattering effect is quite similar to th e effect of nonmagnetic scattering. Remarkably, the ferromagnetic exch ange interaction could lead to the strong resemblance of the conductan ce behavior between a normal-metal-s-wave superconductor junction cont aining a ferromagnet layer and a normal-metal-d-wave superconductor wi th a nonmagnetic scattering layer, and vice versa. This result may com plicate significantly the decisive determination of the pairing symmet ry in high-T-c superconductors by the quasiparticle tunneling into the superconductor. In addition, the resonance peak splitting in the cond uctance is exhibited if the ferromagnet layer is located several super conducting coherence lengths away from the normal-metal-superconductor interface.