Structural characterization of the epitaxially grown core–shell ZnTe/ZnMgTe nanowires

• The epitaxial character of the shells has been confirmed in all studied samples.
• The existence of the tensile strain inside the ZnTe cores has been proven.
• The possible mechanism of the strain creation has been proposed.
• The advantages of the use of combine methods of structural studies have been shown.

We report the method of the epitaxial growth of the core–shell ZnTe/ZnMgTe nanowires. The morphology and the crystal structure of several samples grown in different processes have been studied by scanning electron microscopy, high resolution transmission electron microscopy and X-ray diffraction methods. It was shown that the ZnMgTe shell growth was clearly epitaxial with a good crystal quality. The average lattice spacing of the ZnTe cores and ZnMgTe shells have been calculated and Mg content in the shells has been estimated. It was documented that growing the shell lattice mismatched to the core induces the strain in the core. The model of the strain creation mechanism has been proposed. The presence of a shell with a larger energy gap than that of the core results in a strong emission in the spectral region near the band edge.