Effect of a magnetic field on tunneling conductance in normal metal d-wave superconductor interfaces

Abstract

Through the analytic solutions of the Bogoliubov de Gennes (BdG) equations the effect of a static and homogeneous magnetic field applied parallel to the interface of an NIS (N: Normal metal, S: superconductor and I: Insulator) junction on the differential conductance is calculated. For a d xy -symmetry we obtain zero bias conductance peak that can be split by a magnetic field. The shift of the zero bias conductance peak depends on the spread (β) of the tunneling electrons in k space, on the magnitude of the applied field H and on the ratio between the Fermi energy of the superconductor and the normal region, E FS /E FN . Finally we estimate the minimum value of the magnetic field, H min , that splits the zero bias conductance peak. In general H min depends on β, E FS /E FN , the strength of the insulating barrier Z and on the temperature T .