Solitons supported by competing nonlinearity, higher order dispersion and [formula omitted]-symmetric potential

Abstract

The existence and stability properties of optical solitons in competing cubic-quintic nonlinearity, third order dispersion and parity-time symmetric potentials are investigated. The complex potentials are found as solutions of an inverse problem which predicts explicit expression of the complex potential supporting a required phase gradient structure. It has been found that interplay of competing nonlinearity, third order dispersion, spatial modulation of the refractive index and associated gain/loss profile can give rise to stable solitons in some parameter regimes. Also the solitons are stable even when the parity-time symmetry of underlying linear model is broken. Nonlinear mode excitations have been shown by adiabatic change of the third order dispersion coefficient (which in turn changes the refractive index and gain/loss distribution) whereby a stable nonlinear mode in the parameter domain where the linear PT symmetric phase is unbroken, is excited to another stable nonlinear mode belonging to the parameter domain where linear PT symmetric phase is broken.