Influence of the Kerr effect on the properties of nonlinear PT-symmetric structures

This paper presents a theoretical analysis of the influence of the Kerr and gain/loss saturation effects on the output intensities of PT-symmetric structures. The analysis uses a modified transfer matrix method and allows for investigating how both of the mentioned nonlinear effects simultaneously change a longitudinal field distribution. It was shown that the Kerr effect strongly modifies the output intensity curves in the range of high incident wave intensity values: the characteristics' slope decreases, and oscillations appear. Moreover, in certain cases, the increase in the Kerr effect leads to the disappearance of bistability resulting from gain/loss saturation.