A supersymmetric AKNS problem and its Darboux-B\"acklund transformations and discrete systems

In this paper, we consider a supersymmetric AKNS spectral problem. Two elementary and a binary Darboux transformations are constructed. By means of reductions, Darboux and B\"acklund transformations are given for the supersymmetric modified Korteweg-de Vries, sinh-Gordon and nonlinear Schr\"odinger equations. These Darboux and B\"acklund transformations are adopted for the constructions of integrable discrete super systems, and both semi-discrete and fully discrete systems are presented. Also, the continuum limits of the relevant discrete systems are worked out.