Highly efficient InGaAs/InAIAs MQW waveguide phase shifter

Characteristics of an optical waveguide phase shifter that uses field-induced variation of the refractive index change in reverse-biased PIN InGaAs/InAlAs multiple quantum wells (MQWs) are reported for the first time. High mesa waveguides are fabricated by molecular beam epitaxy and wet chemical etching. The largest phase-shifting efficiency (66° / V mm) ever reported in a reverse-biased structure operating at long wavelengths is obtained near the bandgap; however, this is located in a low absorption wavelength region.