Mode engineering for hybrid SOI/III-V optical devices

Optical amplifiers are demonstrated by direct bonding III–V gain layers to SOI waveguides which include 2-D and 3-D adiabatic tapers. The 3-D tapers have a low loss of 0.1 dB per mode conversion, the lowest demonstrated for coupling between SOI waveguides of this type. The 2-D tapers are used to control interaction with the III–V gain region. An integrated amplifier delivered 14 dB intrachip gain using the new adiabatic tapered waveguides.