TRANSFER-MATRIX AND MATRIX GREEN-FUNCTION - THE MATCHING PROBLEM

The connection between the Green function and the transfer matrix is extended beyond the case of one single differential equation – e.g. a one band model. The Surface Green Function Matching analysis is thus performed in terms of transfer matrices when the Green functions involved are matrices. The practical use of the formalism is demonstrated by studying two physical problems. One is the spatial analysis of proximity effects associated with elementary excitations in a superconductor in contact with a normal metal or a different superconductor. The other one is a calculation of electronic states in semiconductor superlattices made of lead salts. © 1990 IOP Publishing Ltd.