Study of characteristics of MMI devices using matrix approach

Multimode Interference devices are analyzed semi-analytically using matrix approach. The propagation constant and mode profile of different modes of a multimode waveguide are determined. The field intensity for the combination of all the modes at different propagation distance is also obtained. The results are in accordance to the theory. The method can be extended to a singlemode-multimode-singlemode device where the concept of overlap integral is introduced at their interface. As this method consists of multiplication of 2X2 matrices, it is simple and computationally fast