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Lead telluride and germanium telluride are well-known IV-VI semiconductors, which is now the focus of research due to the perspective of application as thermoelectrics for midrange temperatures. Solid solutions and heterostructures on this basis, obtained by molecular beam epitaxy, are a promising direction for the development of these materials. In this paper, we have focused on the Raman spectra excited by the 514.5 nm laser line (out of resonance) of PbTe, GeTe, (Pb, Ge)Te, and (Pb, Ge, Eu)Te layers grown on BaF2 (111) monocrystalline substrates. The obtained phonon properties are related to the properties of the corresponding bulk materials or can be explained by a model that takes into account the difference in the masses of the constituent elements only, as is the case with the local mode of Ge in PbTe (registered at about 181 cm−1). Multiphonon processes registered for this phonon are a consequence of the change in the electronic structure of PbTe and electron-phonon interaction. An improvement in the quality of thin films due to doping with Eu ions was also registered. [ABSTRACT FROM AUTHOR]

The electron spin resonance, magnetization, and dynamic magnetic susceptibility of In1 – xMnxSe layered crystals (x = 0.0125) are studied. It is found that two different impurity subsystems independently coexist in the crystalline layer and in the interlayer spacing of unannealed samples. In both subsystems, ferromagnetic exchange interaction occurs between the Mn ions in the temperature range 300–140 K, and antiferromagnetic interaction occurs in the range 140–77 K. At temperatures below 77 K, a three-dimensional ferromagnetic order emerges. © 2005 Pleiades Publishing, Inc. [ABSTRACT FROM AUTHOR]