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941.
Potassium aluminophosphate glass with the composition 30 K2O-20 Al2O3-50 P2O5 (wt %) doped with four-valence vanadium was prepared and analyzed. Some physicochemical properties of the glass obtained
and its absorption and luminescence spectra were investigated at 300 K. The existence of oxovanadium ions in the prepared
glass was proved on the basis of the electronic absorption data. The bands observed in the electronic absorption spectrum
were assigned to the e→b
1 and e→a
1 transitions. Intense luminescence of four-valence vanadium in the wavelength range 800–1100 nm was found. The average luminescence
decay time amounts to 12 μs.
__________
Translated from Optika i Spektroskopiya, Vol. 96, No. 6, 2004, pp. 926–928.
Original Russian Text Copyright ? 2004 by Batyaev, Linnikov, Lipatova. 相似文献
942.
The kinetics of decay of a phase hologram in a semiconductor CdF2 crystal with bistable In centers is studied. Kinetic constants of the hologram decay are found, and the potential relief of the bistable center is plotted. The resolving power of the crystal is evaluated and recording of a transparency is demonstrated. 相似文献
943.
Experimental dependences of the doubly charged ion yield N 2+ on the laser radiation intensity F are analyzed for the case of ion formation by the two-electron mechanism. It is shown that the region where the dependence N 2+(F) is characterized by the degree of nonlinearity K≈2.5 corresponds to the saturation of the process of doubly charged ion formation. This region is described well by theoretical calculations performed for Gaussian laser beams. 相似文献
944.
945.
Computer processing of electronic absorption spectra of rare-earth elements in inorganic laser media
Algorithms and program modules are developed for calculation of the Judd-Ofelt parameters on modern computers. These programs can be used to perform numerical analysis of the energy absorption by rareearth ions in laser media. 相似文献
946.
947.
The rate-dependent effects in metallic ferromagnetic materials with magnetization processes attributed to domain-walls motion were studied. The experimental method for eddy-current relaxation time determination was proposed. Some discrepancies between the data and theoretical predictions were observed and discussed. The origin of these discrepancies is accounted for by the decrease of viscous-type relaxation process as the rate of change of averaged magnetization is approaching zero. 相似文献
948.
949.
It is experimentally demonstrated that second-order polarizability gratings preliminarily recorded using bichromatic light in a phosphate glass can be amplified under the action of monochromatic radiation. The amplification effect takes place irrespective of the polarization and direction of propagation of the amplifying radiation and is achieved at various wavelengths. The phenomenon is related to the asymmetry of optical transitions between local centers in an isotropic medium in the presence of electric field. It is theoretically shown that this system may feature the formation of alternating electric field domains with dimensions depending on the grating amplitude. 相似文献
950.
A fractal-like structure of the domain boundaries was revealed in “overcritical” uniaxial Permalloy magnetic films. The fractal dimension of domain boundaries at the film surfaces was determined as a function of the film thickness. It is shown that the phase transition between the two possible types of fractal-like structures is accompanied by a jump in fractal dimension.
相似文献