Abstract
This paper recovers cubic–quartic optical solitons for perturbed Fokas–Lenells equation in polarization-preserving fibers and birefringent fibers. The perturbation terms appear with maximum permissible intensity. Singular and dark solitons, together with a few combo solitons, emerge from the sine–Gordon equation integration scheme.
•Cubic–quartic optical solitons are recovered.•The perturbed Fokas–Lenells equation is studied.•The sine–Gordon equation method is adopted.