Comparison of quantum wells based on InGaAs(P)/InP and InGa(Al)As/InAlAs material systems in view of carrier escape times for high-saturation-optical-power electroabsorption modulators

Abstract

We compare electroabsorption modulators (EAMs) with multiple quantum wells (MQWs) based on InGaAs(P)/InP and InGa(Al)As/InAlAs material systems. We carefully choose the quantum-well structures so that the structures based on different material systems have similar band-offset energies and excition-peak wavelengths. Assuming the same light wavelength of 1.55 mu m, we show the transfer functions of EAMs with each quantum-well structure and calculate the escape times of photogenerated charge carriers. As the heavy-hole escape time of the quantum well based on InGaAs(P)/InP is much longer than those of photogenerated charge carriers of InGa(AI)As/InAlAs, the EAM based on the InGa(AI)As/InAlAs material seems to be more suitable for high-optical-power operation.