Interaction dynamics of optical dark bound solitons for a defocusing Lakshmanan-Porsezian-Daniel equation.

We investigate the propagation and interaction dynamics of the optical dark bound solitons for the defocusing Lakshmanan-Porsezian-Daniel equation, which is a physically relevant generalization of the nonlinear Schrödinger equation involving the higher-order effects. Explicit N-dark soliton solutions in the compact determinant form are constructed via the binary Darboux transformation method. Bound states of the dark solitons are discussed when the incoherent solitons have the same velocity.