We have shown that in spatial structures based on color centers created by electrons in a lithium fluoride crystal, the distances between centers reach 1.6 nm and 3.6 nm for F 1 and F 2 centers respectively. This suggests considerable potential opportunities for using electron technology to form structures in the crystals with spatial resolution of such an order of magnitude. We measured the decrease in fluorine content on the irradiated surface of the crystal. We found the concentrations of F 1 , F 2 , F 3 + , F 3 (R 2 ), and F 4 (N 1 ) centers. We established that the specific characteristics of color center formation by electrons leads to an increase in the efficiency of creation of F 3 and F 4 centers. We determined the decrease in the average luminescence lifetimes of F 2 and F 3 + centers as a result of concentration quenching. We observed distortion of the luminescence con- tour for F 2 centers as a result of absorption of its short-wavelength portion by other centers and emission of radiation by the latter in its long-wavelength portion.Introduction. Formation processes, properties, and characteristics of nanosized media and structures and also the prospects for development of nanotechnologies are quite timely problems which are widely studied today. In this paper, we study and discuss the possibilities for creating nanostructures in crystals when they are bombarded by electrons. Electron bombardment leads to formation of intrinsic radiation-induced color centers in crystals and crystalline films [1]. Color centers considerably alter the optical and other characteristics of crystals and films at the sites where they are located, which makes it possible to form certain structures by controlling the spatial distribution of centers. In [2,3], it is suggested that technologies based on creating color centers by an electron beam be used for fabrication of optics devices with high spatial resolution: photomask templates for microelectronics, waveguides, etc. A review of the first research steps in this direction is given in [4].The spatial resolution of elements in structures created by the indicated method is limited in principle by the sizes of the color centers and the linear resolution limits attainable in electron optics. The sizes of color centers are equal to a few interatomic distances in the crystal in which they are formed. Thus using color centers to form structures or record information makes it possible to achieve the highest possible spatial resolution, limited by the atomic structure of the solid. For example, the distance between adjacent atoms in lithium fluoride crystals (LiF), which we used to conduct all the experiments in this work, is 0.2 nm. Consequently, the size of a single element of the structure created by the color center is equal to ≈1 nm. This is much greater than the possibilities for all media for image recording known at this time.The limiting linear resolution in optics, including electron optics, is directly proportional to the wavelength of the radiation used. The de Broglie...

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We have developed quantitative luminescent analysis methods not requiring the use of reference media with known contents of the analyte components. The methods are based on relations describing re-absorption of luminescence and also on a relation connecting the luminescence intensity and the absorption coefficients of a multicomponent medium. We present equations allowing us to find the absorption coefficients and consequently the concentrations of the components of the medium from the luminescence intensity measured in relative units. In order to determine the concentrations of nonluminescent components, we also propose and demonstrate the use of a luminescent probe. We present the experimental results for determination of the absorption coefficients and the concentrations of substances by the methods we developed.Introduction. In luminescent analysis, the presence and concentration of substances are determined from the luminescence spectrum and intensity. For absorption optical densities that are small compared with unity, the photoluminescence (PL) intensity can be assumed to be proportional to the absorption coefficient k 0 , which is uniquely connected with the concentration of the corresponding component of the medium. Therefore from the changes in the intensity in such a case, we can judge changes in the concentration of the substance, which allows us to follow the temporal kinetics of various processes such as chemical reactions. If the condition that the optical density be small is not met, then the photoluminescence intensity cannot be assumed to be proportional to the concentration. Intensity measurements are usually made in relative units and within a small solid angle, the size of which often is difficult to determine sufficiently accurately. Therefore even in the most favorable cases, when carrying out quantitative luminescent analysis we need to use reference media with known content of the components.Luminescent study methods are widely used in scientific practice [1][2][3][4]. They have high sensitivity. There is a large selection of instruments for such studies. However, quantitative luminescent analysis is practically not used due to difficulties in its implementation. This paper is devoted to development of new quantitative luminescent analysis methods. The fundamental difference between our methods and existing methods is the fact that they do not require reference samples, even though they are based on measurements of the photoluminescence intensity in relative units. We have also developed a luminescent probe method which expands the possibilities for analysis, allowing us to use it for nonluminescent substances. The proposed methods are based on analytical relations connecting the photoluminescence intensity and the absorption coefficient of the medium. Such relations have been obtained recently for photoluminescence and photoluminescence excitation (PLE) spectra. In the first case, equations are used that determine the changes in the photoluminescence intensities as a result of re-absorpt...