Laser-induced white emission of diamond was investigated under irradiation with a focused beam of an infrared laser diode. It is a surface-related coherent emission, characterized by an excitation threshold and an exponential dependence on pumping laser power. The mechanism of white emission is discussed in terms of multiphoton ionization of carbon atoms in an irradiated spot. The excitation power dependence of white emission intensity has demonstrated hysteresis loop behavior. This phenomenon could be useful in new broadband laser sources and optical information storage.

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The kinetics of the h -BN c-BN transformation in a mixture of composition 78% h -BN + 5% NH 4 F + 2% B + 15% Mg are studied at 5 GPa and temperatures from 1670 to 1910 K. The activation energy of c -BN formation, temperature-dependent reaction rate constant, strength of the forming c-BN particles, and density of paramagnetic defects in c-BN are evaluated.

The starting ternary compounds CuInS 2 and CuSbS 2 and alloys of the CuSbS 2 -CuInS 2 system with the molar fractions of CuInS 2 (x) equal to 0. 05, 0.15, 0.25, 0.375, 0.50, 0.625, 0.75, 0.85, and 0.95 were prepared and the phase relations in this system were investigated by X-ray powder diffraction, optical microscopy, scanning electron microscopy, and differential thermal analysis. It was shown that the T-x phase diagram of the CuInS 2 -CuSbS 2 system has a eutectic character with the eutectic temperature of 807 K. The alloys of the CuSbS 2 -CuInS 2 system with the molar fraction of CuInS 2 in the range from 0.038 to 0.941 at room temperature are two-phased, and the limits of solubility are 0.059 molar fractions for CuSbS 2 in CuInS 2 and 0.038 molar fractions for CuInS 2 in CuSbS 2 .