Abstract

Carrier confinement in semiconductor quantum wells(QWs) results in extremely large exciton binding energy and oscillator strength when compared with those of bulk crystals. Under an electric field applied perpendicular to the QW layer, the energy of the fundamental absorption edge shifts by a large amount without severe line broadening of the exciton resonance. This well-known quantum-confined Stark effect(QCSE) enables one to utilize QWs for high-speed optical waveguide modulators. Recently, not only QWs with rectangular potential shape, but also several kinds of QWs with modified potential shapes have been studied both theoretically [1,2] and experimentally [3,4], but none of them exhibit polarization-independent electric-field-induced optical effects.

© 1991 Optical Society of America