Jackiw-Rebbi states and trivial states in interfaced binary waveguide arrays with cubic-quintic nonlinearity

We systematically investigate two types of localized states - one is the optical analog of the quantum relativistic Jackiw-Rebbi states and the other is the trivial localized state - in interfaced binary waveguide arrays in the presence of cubic-quintic nonlinearity. By using the shooting method, we can exactly calculate the profiles of these nonlinear localized states. Like in the case with Kerr nonlinearity, we demonstrate that these localized states with cubic-quintic nonlinearity also have an extraordinary property, which completely differs from many well-known nonlinear localized structures in other media. Specifically, both the peak amplitude and transverse dimension of these nonlinear localized states can increase at the same time. Apart from that, we show that high values of the saturation nonlinearity parameter can help to generate and stabilize the intense localized states during propagation, especially in the case with a negative coefficient for the cubic nonlinearity term. © 2020 Author(s).