Darboux transformations for a system of coupled discrete Schrodinger equations

Darboux transformations and a factorization procedure are presented for a system of coupled finite-difference Schrodinger equations. The conformity between generalized Darboux transformations and the factorization method is established. Factorization chains and consequences of Darboux transformations are obtained for a system of coupled discrete Schrodinger equations. The proposed approach permits constructing a new series of potential matrices with known spectral characteristics for which coupled-channel discrete Schrodinger equations have exact solutions. (C) 2002 MAIK "Nauka/Interperiodica".