Compact and Broadband 1 × 4 Optical Switch Based on W2 Photonic Crystal Waveguides

We demonstrate a compact and broadband 1 × 4 optical switch based on W2 photonic crystal waveguides (PCWs). The footprint of the W2 PCW is only 17.6 μm × 8 μm. An operation bandwidth of 15 nm ± 1 nm is implemented with an extinction ratio over 15 dB in each channel. By introducing the thermal insulation trench, the tuning efficiency is enhanced at least 77% in experiment. The experimental results indicate the potential of the proposed broadband thermo-optic switch in silicon on-chip interconnects.