Suppression of symmetry breaking bifurcation of solitons by fourth-order diffraction in a parity-time symmetric potential

In this work, we investigate the existence of symmetry breaking of solitons in optical waveguides with a special Wadati type parity-time (PT) symmetric potential in cubic–quintic media with fourth-order diffraction (FOD). It is further demonstrated that this symmetry breaking can be completely suppressed by tuning the strength of FOD. Moreover, the effects of FOD on linear and nonlinear stability dynamics of the PT-symmetric solitons are examined by their linear spectra and nonlinear evolution simulations, respectively. It is observed that both linear and nonlinear stability dynamics of solitons are improved as the strength of the FOD increases. The change in the shape of solitons due to the presence of the FOD in the system is also discussed.