Material Nonlinearity

To run nonlinear FDTD simulations, you can define material nonlinear models. To do so, in the medium definitions, you have to check the Nonlinearity Specification option and set the following parameters:

Nonlinear Models

models: Use the checkboxes to select the desired nonlinear models. Nonlinear models of different types are additive.

Options:

• NonlinearSusceptibility
• TwoPhotonAbsorption
• KerrNonlinearity

Iterations

num_iters: Number of iterations for solving nonlinear constitutive relation. The nonlinear constitutive relation is solved iteratively; it may not converge for strong nonlinearities. Increasing num_iters can help with convergence.

Type: integer number

• Unit: unitless
• Constraint: greater than 0
• Default: 5

Notes

• Currently, only these mediums support nonlinear models:
  • Medium
  • Debye
  • Drude
  • Lorentz
  • Pole Residue
  • Sellmeier
• Nonlinear mediums do not support Subpixel Averaging.
• Nonlinearity and Space-Time Modulation are not simultaneously supported.

Related Content:

• Bistability in photonic crystal microcavities (opens new window)
• Modeling dispersive materials (opens new window)