Proposal of novel InGaAsP/InP multi-mode interference photonic switches

We propose novel InGaAsP/InP semiconductor photonic switches using multi-mode interference (MIPS). Switching functions are controlled by changing the refractive indices of the index-modulated regions which are located at the center of the multi-mode waveguide. It is predicted from the calculations by FD-TD (finite difference time domain) method that these devices can operate in various kinds of output schemes, with device sizes of about 8 /spl mu/m wide and 540 /spl mu/m long. The characteristics can be improved by optimizing cladding index and/or index-modulated region's width. We fabricated the InGaAsP/InP MIPS with partial current injection regions, and preliminary transmission properties with no index change were observed.