Valence band mixing in charged self‐assembled quantum dots

Abstract

Abstract We analyze the optical emission of neutral, positively and negatively charged excitons in single II‐VI quantum dots presenting a high degree of linear polarization. This linear polarization is attributed to a valence band mixing and we show that in QDs combining both a shape anisotropy and an anisotropic in‐plane strain distribution, the linear polarization direction of the exciton are controlled by an interplay of the valence band mixing and e‐h exchange interaction. Similarly, under strong transverse magnetic field, the direction of the linearly polarized emission of the charged excitons are simultaneously controlled by the valence band mixing and the direction of the magnetic field. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)