The importance of self-consistency in determining interface properties of SIN and DIN structures

We develop a method to solve the Bogoliubov-de Gennes equation for supercon ductors self-consistently, using the recursion method. The method allows th e pairing interaction to be either local or nonlocal corresponding to s-and d-wave superconductivity, respectively. Using this method, we examine the properties of various SW and DIN interfaces. In particular, we self-consist ently calculate the spatially varying density of states and the superconduc ting order parameter. We see that changing the strength of the insulating b arrier at the interface, does not, in the case of an s-wave superconductor, dramatically change the low-energy local density of states in the supercon ducting region near the interface. This is in stark contrast to what we see in the case of a DIN interface where the local particle density of states is changed dramatically. Hence we deduce that in calculating such propertie s as the conductance of SIN and DIN structures it is far more important to carry out self-consistent calculations in the d-wave case. (C) 1999 Academi c Press.