Polymer Mode Selecting Switch Based on Cascaded MMI Couplers

A polymer waveguide mode selecting switch (MSS) composed of two cascaded MMI couplers is demonstrated. The MSS can switch different data channels over E₀₀ and E₁₀ modes. Polymer waveguide dimensions are optimized with beam propagation method. The simulated results indicate that the worst insertion loss is 5.5 dB at 1550 nm and the switching powers for E₁₀ mode between two different channels are 4.5 and 12.3 mW, respectively. The extinction ratio and crosstalk are less than 19.7 and -19.6 dB, respectively. The switching performances of fabricated MSS prove the functionality of proposed design, which promises its potentials in mode-division-multiplexing applications.