Symmetric and antisymmetric solitons in the fractional nonlinear schro•dinger equation with saturable nonlinearity and PT-symmetric potential: Stability and dynamics

We report symmetric and antisymmetric solitons in the fractional nonlinear Schrodinger equation with the defocused saturable nonlinearity and the PT-symmetric potential. Both symmetric and antisymmetric solitons can exist and maintain their symmetries as the power of the soliton increases. We find that the strong saturable nonlinearity suppresses the change of the propagation constant as the soliton power increases. The stability of symmetric and antisymmetric solitons is studied by the linear stability analysis and also verified by the direct numerical simulation. The results show that the high soliton power and strong saturable nonlinearity can restrain the instability of symmetric solitons, and make symmetric solitons propagate stably and possess strong robustness. However, antisymmetric solitons become very unstable and possess less robust with the increase of the soliton power.

Automated summary

This study reports symmetric and antisymmetric solitons in the fractional nonlinear Schrodinger equation with defocused saturable nonlinearity and PT-symmetric potential. It is found that strong saturable nonlinearity suppresses the change of propagation constant as soliton power increases. The stability of symmetric and antisymmetric solitons is analyzed and verified, showing that high power and strong nonlinearity can enhance the stability of symmetric solitons but make antisymmetric solitons unstable.