The mixed discrete modified Korteweg–de Vries (mKdV) hierarchy and the Lax pair are derived. The hierarchy related to the Ablowitz–Ladik spectral problem is reduced to the isospectral discrete mKdV hierarchy and to the non-isospectral discrete mKdV hierarchy. N-soliton solutions of the hierarchies are obtained through inverse scattering transform.

Multisoliton solutions are derived for a general nonlinear Schrödinger equation with derivative by using Hirota's approach. The dynamics of one-soliton solution and two-soliton interactions are also illustrated. The considered equation can reduce to nonlinear Schrödinger equation with derivative as well as the solutions.

In the paper, Ablowitz—Ladik hierarchy with new self-consistent sources is investigated. First the source in the hierarchy is described as φnφn+1, where φn is related to the Ablowitz—Ladik spectral problem, instead of the corresponding adjoint spectral problem. Then by means of the inverse scattering transform, the multi-soliton solutions for the hierarchy are obtained. Two reductions to the discrete mKdV and nonlinear Schrödinger hierarchies with self-consistent sources are considered by using the uniqueness of the Jost functions, as well as their N-soliton solutions.

It is shown that the AKNS hierarchy with self-consistent sources can transform to KN hierarchy with self-consistent sources through a transformation operator and gauge transformation. Besides, there exists transformation in their conservation laws and Hamiltonian structures.