3. Optimizing a Simple MMI 1x2 Splitter

The process for performing optimizations in 3D is very similar to the process in 2D. Refer to the Optimizing a Grating Coupler tutorial and check out the example code for optimizing a 3 dB coupler in 3D at examples/MMI_splitter_3D/mmi_1x2_splitter_3D_fdtd.py.