Full concentration series of tetragonal melilite‐like Ca2−xNdxGa2+xSi1−xO7 single crystals with desordered structure are grown using Czochralski technique and their precies X‐ray structural analysis is carried out. Intensity, absorption, and luminescence characteristics including orientational ones of Nd2+ ions in Ca2Ga2SiO7 are investigated. Using conventional lamp‐pumping technique pulse stimulated emission at the wavelengths of two channels (4F3/2 → 4I11/m, 13/2) is excied and investigated both, at low and room temperatures. Raman spectra of Ca2Ga2SiO7 are also measured.

New germanates with the NdAlGe2O7‐type structure are synthesized. The Czochralski method is used to grow LaGaGe2O7: Nd3+ single crystals and the full concentration series of Gd1−xNdxGaGe2O7 crystals. The GdGaGe2O7 crystal structure is refined. The absorption–luminescence properties of the grown crystals have been studied. The main intensity parameters of luminescence are determined. The stimulated emission of the crystals including that of self‐activated NdGaGe2O7, are excited for two lasing 4F3/2 → 4I11/2 and 4F3/2 → 4I13/2 channels, using the conventional lamppumping technique at 300 K. All the observed induced transitions are identified.

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032ChemInform Abstract The novel germanates LnAlGe2O7 (Ln: Pr, Sm, Eu, Gd, Tb, Dy), LnGaGe2O7 (Ln: La to Dy) and LnFeGe2O7 (Ln: La to Gd) are synthesized by heating stoichiometric mixtures of the oxides to 1100-1300 rc C for 5-10 h. The compound LaGaGe2O7 (I) is studied in detail. Single crystals of (I) and of LaGaGe2O7-Nd3+ (II) with ca. 0.1 at.% of Nd3+ are grown by the method of Czochralski and are characterizedby X-ray analyses. The absorption-luminescence properties and at 300 K the stimulated emission of (II) crystals are studied.

This paper is dedicated to the experimental investigation of laser-induced shock waves impact on electrical, photoelectric and mechanical parameters of narrow-gap Hg 1-x Cd x Te alloys. A mechanism of defect structure rebuilding under the laser shock waves effect is developed. The proposed mechanism manifests itself in one of two dominant ways depending upon the processing mode. The two modes considered involve inducing shock waves by either a single laser pulse or a multi-spike laser pulse.Introduction To study the effect of shock waves (SW) on semiconductors is very important for both fundamental and applied sciences. Laser-induced shock waves (LSW) provide more convenience during experiments in comparison with other SW (burst SW, accelerated electron and ion bombardment SW), because laser processing allows a better control of SW parameters through varying the laser irradiation parameters.It is known that SW propagation through a crystal volume can result in generating different point defects with a concentration reaching 10 -4 at% [1], which causes significant changes in the characteristics of semiconductors as well as of semiconductor devices [2]. This paper focuses on the LSW-defect subsystem interaction in HgCdTe alloy bulk single crystals. The consideration is based on studying the changes of galvanomagnetic, photoelectric and mechanical properties of HgCdTe single crystals caused by LSW processing.