Częstochowa, Poland
Częstochowa, Poland

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Kapustianyk V.,Ivan Franko National University of Lviv | Partyka M.,Ivan Franko National University of Lviv | Rudyk V.,Ivan Franko National University of Lviv | Piasecki M.,ugosz University Of Czestochowa | And 7 more authors.
Journal of Alloys and Compounds | Year: 2010

The absorption spectra of (NH2(C2H5)2)2CuCl4 (DEACC) single crystals and nanocrystals (NC) incorporated into the polymethyl methacrylate (PMMA) polymer matrices were investigated both experimentally and theoretically. It was established that the crystal field spectra of Cu2+ ion detect clearly the quantum size effects. The observed spectra were analyzed using first principle crystal field quantum chemical calculations. It was shown that incorporation of NCs into the polymer matrix allows to identify the charge-transfer (CT) bands in the spectra of DEACC crystals. © 2009 Elsevier B.V. All rights reserved.


Weglowski R.,Military University of Technology | Klosowicz S.J.,Military University of Technology | Majchrowski A.,Military University of Technology | Tkaczyk S.,ugosz University Of Czestochowa | And 3 more authors.
Materials Letters | Year: 2010

We have established a substantial enhancement of Kerr coefficients for 1150 nm cw He-Ne laser wavelength using BiB3O6 (BiBO) nanocrystallites (NC) incorporated into polymer-dispersed liquid crystal composites (PDLC). For this reason we have used 3% and 5.2% in weighting units of BiBO NC possessing sizes varying within the 60-90 nm. It was discovered that BiBO NC may be used for effective gain of Kerr electro-optical susceptibilities varying by the content of the NC at T = 77 K. Moreover, an increase of the Kerr coefficients correlates with decreasing dc-current under applied voltage. The maximally achieved value of the Kerr coefficients were equal to about 1.2·10- 9 m V- 2 (λ = 1150 nm) corresponding to BiBO content equal to about 3%. Such polymer nanocomposites may be considered as perspective materials for the electro-optical Kerr modulators. © 2010 Elsevier B.V. All rights reserved.


Kassab L.R.P.,São Paulo State Technological College | K. Ozga,Czestochowa Technological University | Da Silva D.M.,University of Sao Paulo | Miedzinski R.,ugosz University Of Czestochowa | Slezak A.,Czestochowa Technological University
Optics Communications | Year: 2010

We have found photoinduced second harmonic generation at wavelength 1064 nm during bicolor Nd:YAG laser coherent treatment of TeO2-ZnO and GeO2-PbO amorphous films. The maximally achieved second order susceptibility was equal to about 1.02 pm/V. Correlation of the induced second order susceptibility with local sample heating and induced birefringence may indicate an occurrence of local phase transitions from amorphous glass-like phase to non-centrosymmetry metastable phases. © 2010 Elsevier B.V. All rights reserved.


Krishnakumar V.,Periyar University | Nagalakshmi R.,Periyar University | Manohar S.,Periyar University | Ozga K.,Czestochowa Technological University | And 6 more authors.
International Journal of Modern Physics B | Year: 2010

We have established highly anisotropic features of the piezooptical coefficient behavior in L-lysine monohydrochloride dihydrate (LLMHCl) single crystals (a semiorganic material with space group P21). These coefficients show substantial anisotropy for the diagonal and off-diagonal tensor coefficients. The XRD analysis, FTIR, optical and FT Raman spectra were performed. Following the obtained data, principal role of the phonon sub-system was established. © 2010 World Scientific Publishing Company.


Lavrentyev A.A.,Don State Technical University | Gabrelian B.V.,Don State Technical University | Vu T.V.,Don State Technical University | Shkumat P.N.,Don State Technical University | And 6 more authors.
Inorganic Chemistry | Year: 2016

Density functional theory (DFT) calculations within the concept of the MBJ+U+SO (modified Becke-Johnson potential + U + spin orbit) approach were performed for a Tl4HgBr6 single crystal for the first time assuming weak noncentrosymmetry (space group P4nc). Excellent agreement was achieved between the calculated and experimental band-gap-energy magnitudes as well as the density of electronic states measured by the X-ray photoelectron spectroscopy method. It is a very principal result because usually the DFT calculations underestimate the energy-gap values. In the present study, we carry out calculations of the optical properties (absorption coefficient, real and imaginary parts of the dielectric function, electron energy-loss spectrum, refractive index, extinction coefficient, and optical reflectivity dispersions). It has been established that the principal origin of the observed weak acentricity is determined by delocalized band states at the top of the valence band originating from the p states of the Br atoms. © 2016 American Chemical Society.


Ozga K.,Czestochowa University of Technology | Reshak A.H.,University of South Bohemia | Reshak A.H.,University Malaysia Perlis | Berdowski J.,ugosz University Of Czestochowa | And 4 more authors.
Materials Letters | Year: 2011

We studied an influence of uniaxial pressure on the triglycine selenate single crystals during simultaneous illumination by the continuous wave 532 laser at power about 300 mW. Simultaneously we have studied two-photon absorption for the nanosecond 1064 nm Nd:YAG laser fundamental wavelength. The studies were performed during several cycles of applied uniaxial pressure. A correlation between the photoinduced absorption and the two-photon absorption was found. © 2011 Elsevier B.V.


Reshak A.H.,University of South Bohemia | Reshak A.H.,University Malaysia Perlis | Auluck S.,National Physical Laboratory India | Stys D.,University of South Bohemia | And 4 more authors.
Journal of Materials Chemistry | Year: 2011

A comprehensive experimental and theoretical investigation of dispersion of the linear and nonlinear optical susceptibilities for amino acid l-alanine single crystals is reported. The state-of-the-art full potential linear augmented plane wave method, within a framework of the density functional theory was applied. The atomic positions from X-ray diffraction have been optimized so that the force on each atom is around 1 mRy au-1. This relaxed geometry has been used for the theoretical calculations. The complex dielectric susceptibility dispersion, its zero-frequency limit and the birefringence of amino acid l-alanine single crystals were studied. The crystal exhibits a large uniaxial dielectric anisotropy resulting in a significant birefringence. The calculated birefringence at static limit is 0.072 and 0.074 at λ = 1064 nm (corresponding to 1.165 eV) in good agreement with the measured value (0.073). We also report calculations of the complex second-order optical susceptibility dispersions for the principal tensor components: χ(2)123(ω), χ(2)231(ω) and χ(2)312(ω). The calculated second order susceptibility tensor components χ(2)123(ω), χ(2)231(ω), and χ(2)312(ω) at λ = 1064 nm are compared with those obtained from our measurements performed using the 25 ps Nd:YAG pulsed laser at λ = 1064 nm. Our calculations are in reasonably good agreement with our experimental data. In addition we have calculated the microscopic second order hyperpolarizability, β123, vector component along the principal dipole moment directions for the dominant component χ(2)123(ω) and it is found to be 0.21 × 10 -21 pm V-1 in the static limit and 0.27 × 10 -21 pm V-1 at 1.165 eV (λ = 1064 nm) in comparison with our measured value (0.31 × 10-21 pm V-1) at λ = 1064 nm. Additional study of the second order susceptibilities versus the external laser treatment is performed. © 2011 The Royal Society of Chemistry.


Pisarek J.,ugosz University Of Czestochowa | Piasecki M.,ugosz University Of Czestochowa | Tkaczyk S.,ugosz University Of Czestochowa
Current Applied Physics | Year: 2011

UV 10 ns nitrogen laser pulses at 337 nm give substantial shift of energy gap for LiB3O5 (LBO) nanocrystals (NC) with sizes below 200 nm. The mechanically prepared powders of the NC were put between the MgF2 UV-transparent windows. The power density of the UV-photoinducing beam was varied up to 2.1 GW/cm2. The mechanically prepared LBO NC possessed the sizes varying within the 120 nm-350 nm. The effect exists only for the NC below 190 nm. The photoinduced changes disappeared after about 180 s of switched off of the photoinduced UV beam. For the NC sizes below 125 nm the observed red shift is significantly less. © 2010 Elsevier B.V. All rights reserved.


Kozlowski G.,Wright State University | Miedzinski R.,ugosz University Of Czestochowa | Kleismit R.,Wright State University | Kasperczyk J.,ugosz University Of Czestochowa | And 2 more authors.
Journal of Nano Research | Year: 2013

The topography of indium tin oxide (ITO) films with incorporated silver nanoparticles and irradiated by single pulses of 18 ns Nd:YAG laser has been investigated. The study was carried out with two Ag/ITO films having resistances of 50 Ω and 4 Ω/square sheet resistances. The periodic structures in both samples were created after the laser treatment. The photo-induced periodic structures have a different character while the sheet resistance plays a major role in the growth process of these structures. The results of optical and non-linear optical investigations lead us to the conclusion that the temporary polarization of samples and high temperature of illuminated spot during laser treatment is responsible for the shape of periodic structures. This conclusion has been also confirmed by local permittivity measurements using evanescent microwave microscope and theoretical calculations concerning the temperature distributions during laser illumination. © (2013) Trans Tech Publications, Switzerland.

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