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The influence of dilution by diamagnetic ions on the magnetic ordering in single-crystal CocMg1−cO solid solutions was studied by Raman spectroscopy and magneto-optical microscopy in a wide range of temperatures (6 < T < 200 K). Far infrared absorption measurements of antiferromagnetic resonance (AFMR) were also performed for pure CoO. It was found that the domain structure and the contribution from Brillouin zone center magnons to Raman scattering and AFMR disappear well below the Neel temperature, whose value was determined from neutron diffraction and magnetic susceptibility measurements.

The paper reports on assignment of lattice reflection spectra of the Hg1−x Znx Te alloys (x = 0.10, 0.35, and 0.55) measured in the 40–300-K temperature interval and on a comparative analysis of the lattice vibration parameters for two alloy systems, HgZnTe and HgCdTe, in the low-frequency optical vibration region (the region of the anomalous Hg-Te vibrational mode in HgTe). While the parameters of the fundamental lattice modes are closely similar, the temperature dependences of the low-frequency modes of the two alloy systems are radically different. Their thermal activation energies for the HgZnTe and HgCdTe alloys are 3.3 and 50.0 meV, respectively. The results of the experiment are treated in terms of the double-well potential model for the Hg atom in the alloy lattice.

The IR reflection spectra of structures that consist of alternating layers of CdTe quantum dots and ZnTe barriers and are grown on ZnTe and CdTe/ZnTe buffer layers on GaAs(001) substrates are studied. The spectra are processed using dispersion analysis, and the parameters of the oscillators are determined. In the spectra, quantum dots manifest themselves in the form of a broad band at a frequency close to the frequency of the Frohlich mode. It is revealed that the spectra contain features associated with the interdiffusion of the CdTe and ZnTe compounds, i.e., bands attributed to the local mode of Zn atoms in the CdTe compound and two gap modes of Cd atoms in the ZnTe compound.