Zinc-blende MnTe(111) on BaF2(111) substrates for optical measurements

Thin films of MnTe having zinc-blende structure were grown on BaF2(111) substrates under various growth conditions by molecular beam epitaxy. The structural properties of the deposited films were characterized by x-ray diffraction which evidenced sometimes the presence of other crystallographic phases apart from a dominating zinc-blende-like phase. Detailed measurements of symmetrical and asymmetrical reflections showed that the unit cell of (111) MnTe is not cubic, as is the case of epitaxial (001) MnTe, but it is distorted to an orthorhombic one. The transparent BaF2 substrates enabled optical measurements in transmission, thus, permitting a study of the band structure of the material in the vicinity of its fundamental band gap.