InGaAsP/InP Quantum Well Modulators Grown by Gas Source Molecular Beam Epitaxy.

The quantum confined Stark effect has been studied in InGaAsP/InP rib waveguide structures grown by gas source molecular beam epitaxy. Using 100angstroms wide wells of InGaAs, a room temperature exciton shift of about 250angstroms has been observed for a bias voltage of 6V. At a wavelength of 1.64micron a modulation depth of 35% has been achieved at a frequency of 500MHz. We show that efficient modulation at shorter wavelength cannot be obtained in structures with thinner ternary wells. Instead, we propose and demonstrate InGaAsP modulators operating at a wavelength as short as 1.3micron.