Local Density of States in Anisotropic N-S-N and N-I-S-N Junctions

Abstract

The local density of states of an anisotropic normal metal-superconductor-normal metal and normal metal-insulator-superconductor-normal metal junction is investigated using the Green's function method. The Green's functions are determined by means of the solutions of the Bogoliubov-de Gennes equations for anisotropic superconductors. We find oscillations in the local density of states which in the isotropic case coincide with those found in the Tomasch effect. The local density of states depends on the potential symmetry, the strength of the insulating barrier, and the width of the superconducting region. The influence of different pair potential symmetries on the local density of states is analyzed in detail. In particular, s and d symmetries are considered.