High-performance thermo-optic tunable grating filters based on laterally supported suspended silicon ridge waveguide.

We demonstrate a novel thermally tunable grating optical filter based on suspended silicon ridge waveguide with low power consumption, fast response and relatively high mechanical stability. An enhanced power efficiency of ~300 pm/mW is achieved by employing isolation trench. Periodic lateral tethers and anchors are utilized to support the overall waveguide for maintaining mechanical robustness. 10%-90% rising time and falling time are measured to be 78 μs and 52 μs, respectively. Simulations and experiments both indicate that the demonstrated device has a relatively homogeneous temperature distribution, which is essential for practical integrated photonic devices.