1 × 4 wavelength reconfigurable photonic switch using thermally tuned microring resonators fabricated on silicon substrate

We report a 1 × 4 wavelength reconfigurable photonic switch based on thermally tuned microring resonators (MRs) fabricated on a silicon-on-insulator substrate. The high refractive index of silicon facilitates the formation of highly confined optical waveguides and MRs. With a fabricated ring diameter of about 10 μm, the MRs support 18-nm free-spectral range and 0.15-nm resonant spectral linewidth. Many wavelength channels can be selected through local thermal tuning of resonators for reconfigurable switching and wavelength-division multiplexing/demultiplexing. The switch response time is about 1 ms. The results suggest the feasibility of high port-count photonic circuitry with dynamic wavelength reconfiguration capability for the development of large-scale integrated photonics.