Wydział Fizyki Technicznej, Informatyki i Matematyki Stosowanej / Faculty of Technical Physics, Information Technology and Applied Mathematics / W7

Stały URI zbioruhttp://hdl.handle.net/11652/7

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  • Pozycja
    Frequency dependence of the Kerr constant in nynas nytro 3000 oil determined by the polarimetric method
    (Wydawnictwo Politechniki Łódzkiej, 2018) Poborska, Julita; Dąbrówka, Dominika; Chwirot, Maksymilian; Ledzion, Rafał; Izdebski, Marek; Kucharczyk, Włodzimierz
    Frequency dependence of the Kerr constant in nynas nytro 3000 oil determined by the polarimetric method A frequency dependence of the Kerr constant K in transformer oil Nynas Nytro 3000 within a frequency range 117-5017 Hz is determined. An averaged value (2.30 ± 0.03)·10ˉ¹⁵ m/V² for K is obtained. The constant is found to be weakly frequency dependent and approaches its maximum 2.37·10ˉ¹⁵ m/V² at about 3000 Hz. The Kerr constant is of comparable value to that observed in other mineral oils employed previously in measurements of the quadratic electro-optic effect and the electrostriction in crystals.
  • Pozycja
    Verification of one-dimensional models describing anisotropy of step growth
    (Wydawnictwo Politechniki Łódzkiej, 2017) Izdebski, Marek; Ledzion, Rafał
    Models that allow to obtain directional dependencies of normal velocity of a straight step on the (001) face of Kossel crystal and its edge free energy are reviewed. The dependencies were considered in a wide range of crystal growth conditions, which showed some significant discrepancies between the models and limitations in the scope of their applicability. The results presented concern on one-dimensional kinetic and thermodynamic models of a single step.
  • Pozycja
    Temperature dependence of the Kerr constant of fomblin M03.
    (Wydawnictwo Politechniki Łódzkiej, 2016) Ledzion, Rafał; Górski, Piotr; Izdebski, Marek; Kucharczyk, Włodzimierz
    The Kerr constant B of perfluoropolyether Fomblin M03 has been determined within the temperature range 295-370K. At 300K the constant B was found to be equal to 2.8·10-15 m/V2. The measurements indicate that B varies inversely with temperature. Relatively low electro-optic response of the perfluoropolyether shows its usability in measurements of the quadratic electrooptic effect and the electrostriction in crystals.
  • Pozycja
    Study of electrically induced orientational ordering in mineral oils on the example of orlen oil trafo en.
    (Wydawnictwo Politechniki Łódzkiej, 2016) Izdebski, Marek; Adamus, Monika; Jóźwiak, Ewelina; Ledzion, Rafał
    A simple model of orientational ordering of molecules in the liquid under the influence of an applied sinusoidal electric field of low frequency is presented. The predicted theoretical dependencies of linear birefringence and light transmission coefficients on the intensity of the applied field were confirmed by experimental data obtained for transformer oil ORLEN OIL TRAFO EN. It was found that the intensity of orientational effects in the oil depends strongly not only on the current conditions, but also on the thermal history of the sample. Furthermore it is shown that the minimum amount of dissolved contaminants (e.g. polyethylene) strongly increases the effects. The results suggest that it is necessary to reconsider the techniques for measuring the Kerr effect in liquids associated with deformation of electron cloud, because the traditional approach does not take into account the orientational effects occurring simultaneously with the Kerr effect.
  • Pozycja
    Analytical kinetic block model of crystal-mother-phase multilayer interface.
    (Wydawnictwo Politechniki Łódzkiej, 2015) Organiściak, Maciej; Izdebski, Marek; Ledzion, Rafał
    Simple kinetic block model of multilayer crystal-mother-phase interface is proposed. The model leads to a system of differential equations which can be solved without the need to run Monte Carlo simulations. The proposed model is based on Bragg-Williams approximation (called also zeroth-order approximation), "solid-on-solid" assumption, and other assumptions common with thermodynamic Temkin model. Thus, it is possible to test the compliance of kinetic and thermodynamic approaches in a situation where all other significant differences between models are eliminated. Moreover, a comparison with the results of kinetic Monte Carlo simulations allows for better understanding of the impact of Bragg-Williams approximation.
  • Pozycja
    The impact of aromatic additives on kerr effect in rapeseed oil.
    (Wydawnictwo Politechniki Łódzkiej, 2015) Komenda, Anna; Górski, Piotr; Ledzion, Rafał; Izdebski, Marek
    The Kerr constant and quadratic electro-optic effect were determined for a few different rapeseed oils. The aim of the study was to investigate if aromatic additives in the oil influence its optical properties. Moreover, the effect of ageing of the oils on Kerr phenomena was observed.
  • Pozycja
    Influence of electrode material spacing between electrodes on measurement of Kerr constant in castor oil.
    (Wydawnictwo Politechniki Łódzkiej, 2014) Perek, Artur; Ledzion, Rafał; Izdebski, Marek; Nowakowski, Krystian; Górski, Piotr
    The influence of the electrode material and of the spacing between electrodes on Kerr constant in castor oil is investigated. It is shown that the spacing of the electrodes influences the measurement of Kerr constant whereas the electrode material has no influence on the results of the measurement.
  • Pozycja
    Optimization of measurement conditions of Kerr constant in optical active liquids on the example of castor oil.
    (Wydawnictwo Politechniki Łódzkiej, 2014) Nowakowski, Krystian; Perek, Artur; Izdebski, Marek; Ledzion, Rafał; Górski, Piotr
    The results of measurements of Kerr constant in castor oil, obtained by dynamic-polarimetric method are presented. Variable optical path length and four measurement setup configurations were used. They differed by the orientation of polarizer and of quarterwave plate and therefore they were non-equivalent when other, unwanted effects occurred. It was shown that the Kerr constant measurement performed with use of only one system configuration and one length of optical path may be strongly affected by other effects, however taking the arithmetic mean of two results obtained from appropriate system configurations significantly reduces this error. Theoretical dependences were fitted to the experimental results, which allowed for approximation of other constants, like dichroism, linear birefringence and optical activity induced by external electric field (electrogyration).
  • Pozycja
    Modulation technique used for measurement of very weak linear birefringence and dichroism in liquids on the example of castor oil between metal electrodes.
    (Wydawnictwo Politechniki Łódzkiej, 2014) Izdebski, Marek; Ledzion, Rafał
    A technique for measurement of very weak linear birefringence of the order of 10-7and dichroism in liquids is proposed. The method is based on the polarimetric technique. A characteristic feature is that the experimental setup enables the measurement of linear birefringence combined with electro-optic effect as well as the measurement of dichroism combined with electro-optic effect. The combination of the effect which does not show rapid changes with the effect which depends on alternating electric field allows to improve the sensitivity of the method (in comparison to the earlier static method). This was achieved by use of lock-in amplifier that measures only the selected harmonic with very high selectivity. The theoretical considerations are illustrated by the results of measurements for castor oil.
  • Pozycja
    Estimations of the magnitude of the fourth-order electrooptic effect in KDP-type crystals
    (Lodz University of Technology Press, 2013) Ledzion, Rafał; Izdebski, Marek; Górski, Piotr; Kucharczyk, Włodzimierz
    An attempt to measure the fourth-order electrooptic effect in KH2PO4(KDP) and NH4H2PO4(ADP) is presented. Contrary to previously reported results of the order of magnitude 10-30m4V-4, the fourth-order coefficient |g111111- g221111| is found to be lower than 5 · 10-33m4V-4and 1 · 10-34m4V-4, respectively. In addition, the effect of imperfect crystal cutting and alignment is investigated by means of calculations based on Jones calculus. It is found that even small inaccuracies may lead to an apparent fourth-order electrooptic effect comparable in magnitude to the previously reported values.