We investigate a composite InAsP/InGaAs quantum well in which an 8 nm tensile strained InGaAs well is surrounded by two compressively strained InAsP layers which feature a 70:30 conduction band offset ratio. The composite quantum well is found to provide a high TM differential gain. The InAsP layers provide strain compensation while simultaneously shifting the band gap to the relevant 1.55 µm wavelength region and increasing the electron confinement. Composite InAsP/InGaAs quantum wells are a promising candidate for realizing a polarization independent semiconductor optical amplifier at 1.55 µm.
Haverkort, J. E. M., Dorren, B. H. P., Kemerink, M., Silov, A. Y., & Wolter, J. H. (1999). Design of composite InAsP/InGaAs quantum wells for a 1.55 mu-m polarization independent semiconductor optical amplifier. Applied Physics Letters, 75(18), 2782-2784. https://doi.org/10.1063/1.125148