OptoDesigner Propagation Simulation Modules

2D Eigenmode Expansion Simulations

Eigenmode Expansion (EME) or Bidirectional Eigenmode Propagation (BEP) simulates forward and backward propagation along one axis. It solves Maxwell’s equations in either TE or TM polarizations in the frequency domain and computes the fields at different cross-sections of the device.


The 2D Eigenmode Expansion Simulations Module allows you to simulate single wavelength reflection and transmission along the same axis quickly and reliably.


The BEP method is used for simulations though waveguides and structures where back reflections are required. It supports component simulation and optimization of elements that require both forward and backward direction, such as Bragg gratings, custom Multi Mode Interferometers (MMIs), and polarization components.


  • Visualization and plotting of propagating field components
  • Provides overlap value of the transmission and reflection individually

Figure 1: Top view of a Bragg grating

Figure 2: Side view of a Bragg grating

Figure 3: Result of the BEP propagation simulation in the Bragg gating depicted in Figures 1 and 2

Figure 4: Result of a BEP simulation on an MMI