A Hybrid Silicon–AlGaInAs Phase Modulator

We demonstrate a carrier depletion phase modulator based on the hybrid silicon evanescent platform. A low temperature and robust bonding process is employed to transfer III-V epitaxial layers to patterned silicon waveguides. An external electric field is applied across the doped multiple quantum wells so that carriers are depleted, resulting in an index change. The device has a voltage-length product, V _pi L, of 4 V-mm at 1550 nm. An optical bandwidth of 100 nm with an extinction ratio over 10 dB is achieved. The device can handle optical power up to 28 mW.