A real space approach to study the effect of off-diagonal disorder on superconductivity

We present an efficient numerical methodology to study the effect of off-diagonal randomness on superconductivity. This is a real space approach using Bogoliubov-de-Gennes (BdG) method coupled with augmented space vector recursion (ASVR) technique for disorder averaging. We find in the presence of off-diagonal randomness s-wave superconductivity is favoured by greater hopping integral strength between similar species as compared to that between dissimilar ones and d-wave superconductivity is suppressed by off-diagonal randomness much like diagonal randomness. Combined diagonal and off-diagonal randomness leads to asymmetry in both the normal as well as the superconducting densities of states.