Vector solitons in nonlinear fractional Schrödinger equations with parity-time-symmetric optical lattices

We show that vector solitons can be stable in nonlinear fractional Schrodinger equations with one-dimensional parity-time-symmetric optical lattices. The families of vector solitons with two propagation constants that are present in the different gaps are investigated. It is found that the Levy index cannot change the phase transition point, but it will influence the solitons existence and stability. The effective widths of the two vector soliton components shrink as the Levy index decreases. Some unique soliton propagation properties are found, and soliton propagation simulations are performed to authenticate the results of the stability analyses.