Low-power-consumption integrated tunable filters for WDM switching applications in silicon photonics

We present the experimental results of thermally tunable double microring resonator devices for integrated wavelength division multiplexing applications. The devices demonstrated a free-spectral range up to 2.4 THz (19.2 nm) around 1550 nm and a channel rejection higher than 35 dB. Using Ti/TiN metal heaters, a power consumption of 20 mW per FSR per ring is achieved, which outperformed analogous devices fabricated using the standard silicon process. A thermal tuning efficiency of 0.95 nm/mW is accomplished, and a symmetric tuning is obtained with less than 1% of electrical compensation.