Consider a Si-based MMI structure embedded in SiO₂that operating at the free-space wavelength of 1550 nm, the device has an optional height of 220 nm for 3D simulation.:
(a) The single mode section has a width of 400 nm and the multi-mode section has a width of 10μm. Based on theory, design a 1-to-2 MMI (50/50 power spliter), show detailed work on how to
achieve each value of the design parameters.
(b) Design a 1-to-2 MMI (50/50 power spliter) using BeamPROP. Output the spatial power profile along the direction of propagation and calculate the optical power loss in this process.
Discuss how we can reduce the loss.
(c) Repeat the process in (a) to design a 2-to-2 MMI, where the power from either input will be splitted evenly betweem the two output ports.