Type-II quantum wells with tensile-strained GaAsSb layers for interband cascade lasers with tailored valence band mixing

This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 636930. We would also like to acknowledge the National Science Centre of Poland for support within Grant No. 2014/15/B/ST7/04663.Optical properties of modified type II W-shaped quantum wells have been investigated with the aim to be utilized in interband cascade lasers. The results show that introducing a tensely strained GaAsSb layer, instead of a commonly used compressively strained GaInSb, allows employing the active transition involving valence band states with a significant admixture of the light holes. Theoretical predictions of multiband k·p theory have been experimentally verified by using photoluminescence and polarization dependent photoreflectance measurements. These results open a pathway for practical realization of mid-infrared lasing devices with uncommon polarization properties including, for instance, polarization-independent midinfrared light emitters.Publisher PDFPeer reviewe