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Optical transmission range and phase matching (PM) conditions for second harmonic generation (SHG) of Er3+:YSGG and CO2 laser in indium doped GaSe:In(0.1, 1.23, 2.32 mass%) are studied in comparison with these in pure and sulfur doped GaSe:S(0.09, 0.5, 2.2, 3 mass%) crystals. No changes in transparency curve are found in GaSe crystals up to 2.32 mass% indium content, but as small change as 0.18 degrees in PM angle for 2.79 microm Er3+:YSGG laser SHG and approximately 0.06 degrees for 9.58 microm CO2 laser emission line SHG are detected. PM properties of the crystals are evaluated as a function of temperature over the range from -165 to 230 degrees C. The value of dtheta/dT, the change in PM angle with variation of temperature, is found to be very small for GaSe:In crystals. While for SHG of Er3+:YSGG laser, dtheta/dT =22"/1 degrees C only, it is as small as -4.9"/1 degrees C for that of CO2 laser radiation. Linear variation of PM angle with temperature increasing is an indicator of absence of crystals structure transformation within temperature range from -165 to 230 degrees C. Thus, application of GaSe:In solid solutions in high average power nonlinear optical systems seems to be prospective.

New noncentrosymmetric double borate Rb3EuB6O12 was synthesized by solid state reaction method, and their crystallographic parameters were obtained by Rietveld analysis. This borate crystallizes in the trigonal space group R32 with cell parameters of a = 13.4604(2) Å, c = 30.7981(5) Å, Z = 15. Their structure features a three-dimensional framework composed of [B5O10] 5groups that are bridged by Eu-O polyhedra. The existence of B5O10 group in the structure was confirmed by vibrational spectroscopy. Rb3EuB6O12 melts incongruently at 1101 K. The second harmonic generation effect of Rb3EuB6O12 is 16 times higher than that of α-quartz standard. In the luminescence spectrum, the domination of a single prominent narrow line from hypersensitive 5 D0-7 F2 manifold of Eu 3+ ions is observed, while 5 D0-7 F1 manifold and ultranarrow 5 D0-7 F0 line are of comparable peak intensity. These features are explained by specific local symmetry of Eu ion within the crystal structure of Rb3EuB6O12..

The La(2)O(3)/Si thin films have been deposited by reactive DC magnetron sputtering. Amorphous state of La(2)O(3) layer has been shown by RHEED observation. Top surface chemistry of the a-La(2)O(3) has been evaluated with layer-by-layer depth profiling by ion bombardment and XPS measurements. It was found by core level spectroscopy that the top surface of the a-La(2)O(3) film consists of hydrocarbon admixture, lanthanum carbonate, and hydroxides that formed as a result of contact with air atmosphere. Thickness of this top surface modified layer is below 1 nm for a contact time of ~1.5 h with air at normal conditions.

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