Chirp Parameter in Strained Coupled Quantum Well Electroabsorption Modulators

Abstract

AbstractDependence of chirp parameter of a coupled double quantum well electroabsorption modulator at wavelength 1.55 µm on the structural parameters such as wells widths and strain of wells is studied. For this purpose, we calculate the absorption of structure under applied electric fields and then solve the Kramers-Kronig relation to obtain field-induced refractive index changes. Results show that the chirp parameter is strongly dependent on the first well width and strain variation. The wider well with the compressive strain results in reduction of chirp parameter. The second well parameters effect is weaker than that of the first well. Results show that by proper design of absorption region, all negative chirp can be achieved.