Optical soliton solutions of the time-fractional perturbed Fokas-Lenells equation: Riemann-Liouville fractionalderivative

Based on the Riemann-Liouville fractional derivative, the time-fractional nonlinear Fokas-Lenells equation is analyzed in this paper. The extended simplest equation method is implemented to construct several kinds of solitons such as singular and combo soliton solutions of the present model. The existence criteria of the obtained soliton solutions are also reported. Moreover, it has been shown that the results in the literature are special cases of the present ones when the fractional-order of differentiation becomes unity.