High-confinement SiGe low-loss waveguides for Si-based optoelectronics

The realization of two-dimensional SiGe/Si strained-layer low-loss waveguide (1.7 db/cm) is reported. The waveguide geometry is grown by selective epitaxy. It ensures loosened cutoff and critical thickness conditions. This geometry could be applied for waveguide active devices like light emitting diodes, photodetectors, or modulators. Because of the high cross section of the guided mode, these devices could be easily interfaced with optical fibers.