Characterization of normal and inverted interfaces by the Zeeman effect inCd1−xMnxTe/CdTe/Cd1−yMgyTequantum wells

Abstract

We present a study of the interface profile in asymmetric ${\mathrm{Cd}}_{1\ensuremath{-}x}{\mathrm{Mn}}_{x}{\mathrm{T}\mathrm{e}/\mathrm{C}\mathrm{d}\mathrm{T}\mathrm{e}/\mathrm{C}\mathrm{d}}_{1\ensuremath{-}y}{\mathrm{Mg}}_{y}\mathrm{Te}$ quantum wells, with normal (${\mathrm{Cd}}_{1\ensuremath{-}x}{\mathrm{Mn}}_{x}\mathrm{Te}$ on CdTe) and inverted (CdTe on ${\mathrm{Cd}}_{1\ensuremath{-}x}{\mathrm{Mn}}_{x}\mathrm{Te}$) interfaces. The Zeeman spectra of the confined exciton states were determined by magnetoreflectivity and Kerr rotation measurements. Using a segregation model and an asymmetric exponential profile, we interpret the Zeeman spectra of quantum wells, and determine the interface widths. For the same concentrations of Mn in the barriers and the same growth conditions, the results can be coherently explained assuming an interface width independent of the quantum-well width and the type of interface (normal or inverted).