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Analytical expressions are found for the mobility of a degenerate electron gas in a quantum wire for three scattering mechanisms: on ionized impurities and on piezoacoustic and deformation acoustic phonons. The expressions allow one to analyze the concentration, temperature, and dimensional dependences of the electron mobility.

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The effect of γ ray radiation on the electrical properties of heat treated Tb 0.01 Sn 0.99 Se (sample 1) and Tb 0.05 Sn 0.95 Se (sample 2) samples is studied. It is found that, as a result of irradiation with γ ray 1.25 MeV photons, the charge carrier concentration decreases in the temperature range T = 77-200 K by 17 and 6.3% for samples 1 and 2, respectively. It is assumed that, in the course of irradiation with γ ray photons, terbium impurity atoms are located between sites of the crystal lattice; in addition, Frenkel defects are formed.

In the given paper, the temperature dependences ([Formula: see text]–300 K) of the green band intensity at wavelengths [Formula: see text] nm and [Formula: see text] nm have been measured and observed, respectively, from the polished and unpolished surface (PS and unPS) of a polycrystalline CVD (chemical vapor deposition) ZnSe sample upon excitation by X-ray quanta ([Formula: see text]. In both cases, the activation energy of thermal quenching has been determined, and the reasons for thermal quenching have been considered in detail. Along with XRL spectra analysis, the temperature behavior of the green band observed upon excitation by an ultraviolet (UV) laser (He–Cd, [Formula: see text] nm) from the PS and unPS in the temperature range [Formula: see text]–200 K has been discussed in more detail.

The photoluminescence spectra of CVD (chemical vapour deposition) ZnSe polycrystalline grown with a large excess of selenium and containing \O*Se-Cu+i\ complexes at stacking faults are studied. Absorbance was measured to complement these data. The features of the PL spectra in comparison with cathodoluminescence are considered. It is shown that PL bands identical to CL are observed as somewhat shorter wavelengths. For the studied crystals, a band model is presented according to the data obtained in this work. The low-energy shift of the PL spectra with decreasing excitation energy corresponds to a shift on the energy scale of the band model with a corresponding change in the type of radiative transitions. It is shown that identical photoluminescence bands are observed as somewhat shorter wavelengths than cathodoluminescence bands. For the crystals under study, a band model is presented according to the data obtained in the given decreasing work. The low-energy shift of the photoluminescence spectra upon the excitation energy corresponds to a shift along the energy scale of the band model with a corresponding change in the type of radiative transitions. Changes have been introduced that characterize the nature of the group of equidistant bands 477-490 nm, which are characteristic of ZnSe samples with an excess of oxygen and Se. The results can be useful for a more complete study of the structure of multiphonon exciton spectra of photo and cathodoluminescence of AIIBVI crystals. Keywords: band model, narrow-line multi-photon spectra, exciton radiation, stacking faults, isoelectronic oxygen impurity, carrying effective negative charge.

We present the photoluminescence spectra obtained in the case of normal incidence of exciting radiation at both polished and unpolished surfaces of chemicalvapour deposited ZnSe films in the temperature range 12-300 K. The luminescence has been excited using either a continuous-wave He-Cd laser with the wavelength λ ex = 325 nm (i.e., under the condition hv ex > E g for the photon energy) or a semiconductor laser with λ ex = 532 nm (i.e., hv ex < E g). We show that the temperature dependences of intensity, spectral position and half-width of a green photoluminescence band detected in the both alternative cases are very different in the region 12-80 K. However, their behaviours become very close to each other when the temperature increases up to 180 K. Finally, the above spectral parameters are almost the same in the region 180-300 K.

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