ELECTROABSORPTION AND SATURATION BEHAVIOR OF INGAASP INP/INALAS MULTIPLE SUPERLATTICE ELECTRON-TRANSFER OPTICAL MODULATOR STRUCTURES/

We report substantial progress in the growth of multi-quantum-well ele ctron transfer optical modulator structures by metalorganic vapor phas e epitaxy, which is made possible as a consequence of the highly abrup t modulation doping of donors and acceptors in InP-reservoir and InAlA s-barrier layers, respectively. Due to a large thermionic emission bar rier provided by the type II InP/InAlAs interface, the InGaAsP/InP/InA lAs devices exhibit extremely low leakage current densities. We observ e distinct and sharp features related to absorption quenching in diffe rential transmission spectroscopy. Moreover, the saturation intensitie s of electron transfer modulators are determined. The underlying physi cal mechanism is discussed.