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Unirradiated and γ-irradiated (average energy E = 1.25 MeV and dose Φ = 2.41 MGy) chalcogenide glassy semiconductors (CGSs) As2S3 and Ge15.8As21S63.2 are studied by positron annihilation lifetime spectroscopy (PALS) and Doppler broadening of the 0.511-MeV annihilation line (DBAL). Two 22Na positron sources with activities of 0.6 and 2.0 MBq and Kapton film thicknesses of 8.0 and 25.0 μm, respectively, are used. It is shown that radiation-induced changes in the PALS parameters of the CGS types under study are within measurement errors. The DBAL method appeared more efficient and accurate for studying radiation-stimulated processes in CGSs.

Substrates of chalcogenide glassy semiconductors As2S3 and Ge15.8As21S63.2 are implanted with Cu+ ions (energy 40 keV, radiation dose 1.5 × 1017 ion/cm2, fixed current density in the ion beam 1 μA/cm2). The composite layers are analyzed by measuring linear optical transmittance and recording nonlinear optical absorption using the Z-scan technique at 780 nm (probe laser radiation with 150-fs pulses; intensity of 25–100 mW). It is ascertained for the irradiated materials that (1) the linear transmission characteristic of the optical surface plasmon resonance (SPR) band, which indicates the formation of copper nanoparticles in the near-surface region, has emerged and (2) there are simultaneously saturated and two-photon nonlinear absorption types; the latter prevails as the intensity of laser irradiation is increased.

A technology of intercalation of layered AIIIBVI single crystals by elements of the Fe 3d group during their growth has been developed. The X-ray structural and X-ray phase analyses of the thus-obtained Ni x InSe samples confirmed their homogeneity and showed a nonmonotonic dependence of the InSe lattice parameter along the anisotropy axis on the incorporated Ni concentration. The dependence of the magnetic susceptibility on magnetic field, χ(H), has been studied by the Faraday method, and a nonmonotonic change in χ with an increase in the incorporated nickel concentration has been revealed for Ni x InSe crystals. This nonmonotonicity can be qualitatively explained within a modification of the Anderson model for layered crystals, which takes into account the main specific features of layered crystals and the intercalation mechanism.

The magnetic susceptibilities of Si and Si0.95Ge0.05 alloy whiskers of different diameters have been studied. Its significant difference from the magnetic susceptibility of a bulk material has been found. The presence of paramagnetic centers, some of which form magnetic nanoclusters in samples, is assumed. To explain the experimental results obtained, a model within Langevin superparamagnetism has been suggested. The distribution function of clusters over their magnetic moments has been constructed. The most probable sizes and magnetic moments of clusters are determined.

The principal circuit of a helium ionization detector with a thermionic electron emitter (He-IDTEE) is described. The detector works at atmospheric pressure. The characteristics of the detector were studied. The difference between the voltammetric characteristics of He-IDTEE and that of a helium ionization detector with a radioactive source was shown. The dependences of the analytical signal, background signal, and noise on an accelerating voltage were analyzed. The dependences of the signal-to-noise ratio on the accelerating voltage were studied at different cathode temperatures. The optimal working conditions of the detector were selected. The detection threshold and linear dynamic range were measured. For isobutane, they were 3 × 10−9 vol % and 2–4 orders of magnitude, respectively.

The effect of radiation defects on the field and temperature dependences of the magnetic susceptibility of single-crystal Si was studied. A nonlinear magnetic-field-dependence of the magnetic susceptibility of irradiated Si was observed. This behavior can be explained by magnetic ordering of A centers. It was concluded that clusters of these centers with a local density of the order of 1021 cm−3 exist. An explanation of the “diffusion paradox” in the formation of oxygen-containing thermal donors was proposed on the basis of micrononuniformities of the spatial distribution of thermal donors and interstitial oxygen in Si.

Institute of Physics, Ukrainian National Academy of Sciences, 252650 Kiev, Ukraine Fiz. Tekh. Poluprovodn. 32, 8, 1026 ~August 1998! @S1063-7826~98!02308-4# © 1998 American Institute of Physics. A major correction was reported by the Semiconductors Editorial office in St. Petersburg. Specifically, the title was incorrect. The correct title should read: Magnetic ordering of radiation defects in silicon.