Abstract

Recently, novel multiple quantum well modulators based on voltage-controlled electron transfer between a reservoir and the active layer have been developed for long wavelength applications in both InGaAlAs and InGaAsP alloy systems.^1-3 They outperform current injection devices in terms of energy dissipation and speed,² and deliver comparably large absorptive and refractive modulation. One major drawback of these quantum well based devices has been their distinct polarization dependence, which is disturbing for many important applications such as optical cross-connects. Such a dependence arises owing to the different selection rules for optica] absorption in the waveguide geometry, namely, TE (e-hh, e-lh) and TM (e-lh).

© 1993 Optical Society of America