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vol. 125
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issue 2
638-641
EN
We construct a novel model for a single photon, bearing an internal dynamics. In our model, the photon, while travelling with a speed very close to c (the ultimate speed of light in empty space), is considered to oscillate, in its own frame, with its given frequency f. The envelope of the photon's instantaneous maximum amplitude, which we will call from here on straight "amplitude", is assumed to travel with exactly c, which makes that the center of the photon ought to travel with a speed little less than c. It is interesting to add that, in the present approach, the higher the frequency of the photon at hand, the narrower is its amplitude of oscillation. It is further assumed that the photon has a rest mass which we call "kernel", carrying the translational motion of it. This allows us to estimate the rest mass of the given photon, based on adopted initial conditions of the early universe, based on the recent Yarman and Kholmetskii model (resolving, amongst other things, the dark energy quest). One then comes out with the result that all observable photons (i.e. either high energy gamma rays or very low frequency radio waves), travel practically with the same speed, which is virtually c, the measured ultimate speed. A model regarding the internal dynamics in question is further offered.
2
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Gas Sensors Based on ZnO Structures

80%
EN
The paper presents the results of investigations concerning sensor structures based on porous layers of zinc oxide (ZnO) sensitive to a selected gaseous environment. The investigations comprised analyses of the influence of the gaseous environment on the optical properties of a sensor structure, in particularly on the change of the spectral characteristics of optical transmission within the range of ultraviolet light and in the visible range. These presented investigations were carried out in such a gaseous environment as nitrogen dioxide NO_2 in synthetic air.
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issue 6
1239-1241
EN
The paper deals with investigations concerning a wide-band gap material, viz. zinc oxide ZnO. Special attention has been devoted to the determination of the spectral transmission of zinc oxide layers deposited on quartz substrates. These investigations have made it possible to determine the optical spectral range in which this material is transparent as well as the edges of absorption. The presented investigations are valuable particularly concerning the application of zinc oxide in optoelectronic and photonic structures as well as in systems of waveguides and sensor layers of integrated optics.
EN
The new multi-frequency process, which consists of three coupled nonlinear optical interactions: two parametric down-conversions and one up-conversion, in aperiodically poled nonlinear crystal is investigated. The spatial dynamics of wave intensities is studied in detail. The possibility of secondary simplification of coupled equations for correct describing the dynamics of wave interactions is demonstrated. The optimal conditions for parametrical instability of the initial stage of wave interactions are found.
5
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Inverse Laplace Transform of Some Rational Functions

80%
Acta Physica Polonica A
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2012
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vol. 122
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issue 5
966-968
EN
In this paper we propose a formula of recurrent nature for calculating the inverse Laplace transforms of some rational functions. The procedure and formulae enabling to determine the values of coefficients of obtained series are presented. Proposed procedure does not require any partial fraction decomposition. Moreover, it is proved that the radius of convergence of the received series (for the respective objective function) is equal to infinity. The proposed formula can find applications in wave optics and acoustics.
6
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The Sensitivity of Composite Bimodal Waveguide SU-8

80%
Acta Physica Polonica A
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2013
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vol. 124
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issue 3
602-605
EN
This paper presents the results of measurements of the refractive index and thickness of the waveguide layer SU-8. The mode sensitivity has been calculated as a function of the thickness in a bimodal structure. The differential interference was analyzed concerning modes of the same types TE_0-TE_1 and TM_0-TM_1 and modes of the same order (TE_0-TM_0, TE_1-TM_1). The thickness of the layer was determined when the interferometer is most sensitive to changes of the refractive index. It has been proved that the sensitivity of the structure can be increased by adding a nanometric layer with a high refraction index (n_{A}=1.975) on the waveguide layer.
EN
The goal of this work was to investigate the spectroscopic properties of Pr^{3+} ions (of a comparable concentration of the order of 0.2 mol/dm^3) embedded in the tellurite glass matrix, i.e. TeO_2-WO_3-PbO modified with lanthanum and lutetium oxides. The difference is that the last components of both glasses provide ions which are optically inactive within the 4f shell, since this shell is completely empty for La^{3+} ion and completely filled for Lu^{3+} ion. The absorption and fluorescence spectra of Pr^{3+} doped in tellurite glass has been recorded and analyzed in terms of the Judd-Ofelt theory. The studies of the glasses comprised ellipsometric, spectrophotometric and photoluminescence measurements. The ellipsometric studies yield the refraction index dispersion which appears to be quite similar for all the studied glasses. From the spectrophotometric measurements, the absorption spectra have been obtained which, for Pr^{3+}-doped samples, have been analyzed in terms of the Judd-Ofelt theory. Finally, the photoluminescence studies demonstrate a clear visible emission from ^3P_0 level to lower-lying states of Pr^{3+} ion.
EN
The paper deals with considerations concerning planar waveguide structures, in which the polymer SU8 is used as the waveguide layer. The results of numerical calculations of the distribution of the field concerning structures of various thicknesses have been presented, and photos taken in the course of investigating the surface by means of a microscope of atomic forces. The results of calculations of sensitivity in relation to the refractive index of the cover layer at various thicknesses of the layer have been presented, too.
9
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Planar Optical Waveguides Based on Thin ZnO Layers

61%
EN
The paper quotes the results of investigations concerning planar optical waveguides with a high value of the refractive index, achieved basing on a broad-band gap semiconductor ZnO, deposited on glass or quartz substrates. The investigations were focused on the properties of the waveguides, determining the modal characteristics, the attenuation coefficient and the structure of the surface.
EN
The paper presents the results of investigations concerning the measurement of the attenuation of planar waveguide structures obtained by means of the photopolymerization of the polymer SU8. The applied substrate was sodium-calcium glass. Attenuation is one of the fundamental parameters of optical waveguide, the knowledge of which is of crucial importance in the construction of various kinds of optical sensors. A method of its measurement has been presented, consisting in the recording of the intensity of scattered light making use of CCD camera. The paper deals also with the generation of planar polymer waveguide, taking into account problems connected with the adhesion to glass substrates.
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issue 6
1133-1135
EN
In this paper an analysis of two types of planar waveguides (with the conventional type of the layer and the reverse symmetry waveguide) is presented. In both types of the structure the polymer SU8 was used. In respect of its properties, this polymer is suitable as a waveguide layer. The analysis presented in this paper describes those structures working as sensors. We made a comparison of both types of configuration. We made a detailed analysis of the sensitivity of the covering layer when the thickness of the waveguide layer is changing and when the length of the wave activating the structure is changing, too.
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issue 6
1140-1142
EN
This publication presents experimental measurement methodology which allows to determine the characteristics of sensitivity planar differential interferometer. To confirm data reliability additional measurements were done such as simulations in OptiBPM software by Optiwave. Curves received from two methods: experimental and theoretical, were summed up and compared. Conclusions were made on their basis, for example the influence of used wavelengths or refractive index of single mode waveguide cladding on curves of sensitivity differential interferometer using planar waveguide received from the ion exchange method.
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issue 6
1136-1138
EN
The paper presents results of investigations concerning the measurement of the refractive index and thickness of planar waveguide structures, obtained by the photopolymerization of polymer SU8. Sodium-calcium glass was used as the substrate. As the knowledge of the quoted parameters is from the viewpoint of the structure of various types of optical sensors of crucial importance, the way of their determination has been presented. The paper deals also with the method of constructing planar polymer waveguides, taking into account problems connected with their adhesion to glass substrates.
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