Tunable Silicon-on-Insulator based integrated optical filters with liquid crystal cladding

We investigate the tunability of Silicon-on-Insulator (SOI) devices with liquid crystal (LC) cladding. The tuning mechanism is based on electro-optic response of the cladding to applied external electric field. The validity of this scheme is established using Mach-Zehnder interferometers (MZI). The parameters affecting the tunability of the devices are explored. Up to 20 nm shift of interference wavelength in MZI with a 150 nm thick SOI waveguide by applying 30 V is demonstrated, the highest tunability range in such designs reported to date.