Tuning of photonic crystal waveguide microcavity by thermooptic effect

A tunable photonic crystal microcavity with in-filling holes has been experimentally realized by using the thermooptic effect. in silicon-on-insulator waveguide at lambda = 1530 nm. The device was fabricated by reactive, ion etching through the silicon core layer for high vertical confinement. A thin film heater has been integrated onto the microcavity. A small change in temperature (and consequent change in refractive index) was sufficient to cause an observable resonance shift. A resonance shift of 5 nm was achieved when the heater was switched on to a current of 1.2 mA (with switching power of about 9 mW).