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Częstochowa, Poland

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.

Kassab L.R.P.,Sao 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.

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.

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.

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