Nonlinear light interaction in an array of dielectric subwavelength waveguides

We study the dynamics of nonlinear propagation and interaction of two optical fields in arrays of dielectric subwavelength waveguides of circular cross section. Applying the finite-difference time-domain (FDTD) method, we numerically solve the Maxwell's equations considering real values for the constitutive relations. The arrays under study include a finite number of parallel waveguides with identical parameters. In our study, we focus on the light self-trapping conditions. For that, we define the properties of the incident optical fields: complex amplitude, wavelength, angle of incidence and phase difference values. As a result, we observe the strong dependence of the energy output to input critical parameters: phase difference and angle of incidence. We conclude about the possibility to generate a single output beam. The output signal position depends on the nonlinear interaction properties and is controlled by the selection of the system parameters. These results may contribute to the development of logic gates based on subwavelength waveguides.