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Substitution of Gd 3+ for Eu 2+ ions in EuTe leads to the introduction of Gd 5d electrons to the conduction band and antiferromagnetic order of EuTe (Heisenberg magnetic semiconductor) can be replaced by ferromagnetic state due to RKKY interaction. The layers were grown by MBE method on BaF 2 (1 1 1) substrate. Layer of Te deposited on top of (EuGd)Te protects surface of oxidation. Heating in 320• C leads to Te atoms desorption and to improvement of the layer electronic structure. Additional Gd atoms were sequentially deposited on the layer of (PbGd)Te and set of Fano resonance curves were observed for ions of Gd. The Fano type photoemission resonance corresponding to the 4d-4f transitions were studied for Eu and Gd.

The synchrotron radiation was used to apply tunable high energy X-ray photoemission spectroscopy for investigation of electronic structure of semiconductor nanostructure CdTe/Pb 0.95 Eu 0.05 Te/CdTe/GaAs(001) top part. The Pb 0.95 Eu 0.05 Te (6 nm thick) was buried under thin (22 nm) top layer of CdTe transparent for part of electrons photoemitted from Pb 0.95 Eu 0.05 Te buried layer. The top layer of CdTe was sputtered by Ar ion bombardment for surface cleaning and for leaving the thickness of CdTe more transparent for photoelectrons emitted from buried layer. For these thickness of the top layer the photoemission energy distribution curves corresponding to the valence band and core levels electrons of the buried layer atoms were measured with application of synchrotron radiation of energy hν = 3510 eV. The measured spectra corresponding to the buried layer atoms were observed in the valence band region and in the high binding energy region for core levels of Pb 4f , Pb 3d. The valence band contribution and core levels Cd 4d and Cd 3d were obtained mainly from top cover layer. Measured Te 4d, Te 3d and Te 4d spectra possess contribution as well from top cover layer as from the buried layer. The amount of Eu atoms was to small to be reasonable detected and presented in the paper.

The electronic band structure of Mn/ZnTe(110) (1×1) has been studied by angle-resolved photoelectron spectroscopy. The sets of spectra were acquired for the clean surface and after in situ deposition of 0.4 ML of Mn, in order to compare the band structures and to reveal changes brought about by the presence of Mn. The experimental band structure diagram of Mn/ZnTe along the Γ −K direction in the Brillouin zone has been derived from the experimental data. Indications of interaction between the Mn 3d states and sp 3 bands of the semiconductor are discussed.