Nonlinear dynamics and chaos in dissipative optical trimers with complex couplings.

In the context of non-Hermitian photonics, we consider a nonlinear optical trimer with three lossy waveguides with complex couplings. This non-Hermitian trimer exhibits stable stationary and oscillatory regimes in a wide range of values of the coupling-loss parameters. Moreover, chaotic dynamics through period doubling is confirmed via Lyapunov exponent measurements and the underlying bifurcation structure is found by semianalytical continuation of solutions. The interplay of chaos, due to Kerr nonlinearity, and non-Hermiticity, due to the combined dissipation and complex coupling, provides a different perspective in the area of nonlinear and non-Hermitian optics.