Vector surface solitons in optical lattices with fractional-order diffraction

We report on the existence and stability of mixed-gap vector surface solitons at the interface between a uniform medium and an optical lattice with fractional-order diffraction. Two components of these vector surface solitons arise from the semi-infinite and the first finite gaps of the optical lattices, respectively. It is found that the mixed-gap vector surface solitons can be stable in the nonlinear fractional Schrodinger equations. For some propagation constants of the first component, the stability domain of these vector surface solitons can also be widened by decreasing the Livy index. Moreover, we also perform stability analysis on the vector surface solitons, and it is corroborated by the propagations of the perturbed vector surface solitons. (C) 2020 Optical Society of America