EFFICIENT MODELING OF THE OPTICAL-PROPERTIES OF MQW MODULATORS ON INGAASP WITH ABSORPTION-EDGE MERGING

The optical properties of quantum wells on GaxIn1-xAs1-yPy are investi gated, The dielectric function epsilon(omega) is calculated with a den sity matrix formalism valid for excitonic transitions as well as for t he interband absorption including band mixing, With two simple approxi mations, the required number of overlap integrals is greatly reduced, allowing a fast and efficient exciton calculation. The calculated resu lts are compared with measurements at 77 K and at a room temperature o f 300 K, Furthermore, we present a field-induced heavy and light hole absorption merging for a GaxIn1-xAs1-yPy-based modulator for the first time. It can be operated at a wavelength lambda = 1.55 mu m, showing a very large absorption change and a small negative chirp factor, whic h is recommended for a low bit error rate.