Polarization independent /spl delta/-strained InGaAs/InGaAsP quantum well waveguide modulator

Polarization independent modulators are important devices for optical communication systems operating at 1.55 /spl mu/m. However, conventional unstrained QW modulators, based on the quantum confined Stark effect (QCSE), typically exhibit a strong polarization dependence in transmission due to a strong polarization dependence of the absorption near the band edge. We have demonstrated a /spl delta/-strained InGaAs/InGaAsP MQW polarization independent waveguide modulator. It exhibits excellent polarization insensitivity, high extinction ratio, high speed response and low driving voltage. It shows that the /spl delta/-strained MQW modulator is a promising device for telecommunication applications.