Stability of Optical Solitons in Parity-Time-Symmetric Potentials with Competition Nonlinearity

This study investigates the existence, stability, and propagation of fundamental, dipole, and tripole modes in parity time symmetric potentials with competing cubic and quintic nonlinearities. We discuss such parity time solitons in the presence of a focusing quintic nonlinearity and a defocusing cubic nonlinearity. Assuming a fixed quintic nonlinearity coefficient 02 of 1, these solitons can exist and remain stable within a suitable power range. Fundamental solitons can remain stable even for lower values of sigma iota, while dipole and tripole solitons may only be stable for larger values of 01. By employing appropriate parameters, a significant proportion of solitons can be stabilized. The stability and propagation of the solitons are demonstrated through linear stability analysis and direct numerical simulations.