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Condensed Matter Physics Commons

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Full-Text Articles in Condensed Matter Physics

Optical Properties Of Photopolymerisable Nanocomposites Containing Zeolite Nanoparticles, Izabela Naydenova, Tzvetanka Babeva, Elsa Leite, Nitesh Pandey, Temenujka Yovcheva, Svetlana Mintova, Vincent Toal Jan 2009

Optical Properties Of Photopolymerisable Nanocomposites Containing Zeolite Nanoparticles, Izabela Naydenova, Tzvetanka Babeva, Elsa Leite, Nitesh Pandey, Temenujka Yovcheva, Svetlana Mintova, Vincent Toal

Conference Papers

Acrylamide-based photopolymerisable nanocomposites containing three different types of nanozeolites – Si-MFI, AlPO and BEA, were studied. The influence of the porous nanoparticles on the average refractive index, optical scattering, holographic recording properties and shrinkage were characterised.


Surface Relief Profile Of Photopolymerisable Systems In A Single Illuminated Spot, Tsvetanka Babeva, Dana Mackey, Izabela Naydenova, Suzanne Martin, Vincent Toal Jan 2009

Surface Relief Profile Of Photopolymerisable Systems In A Single Illuminated Spot, Tsvetanka Babeva, Dana Mackey, Izabela Naydenova, Suzanne Martin, Vincent Toal

Conference Papers

The formation of surface relief profile in photopolymerisable systems when illuminated with a focused beam of light is simulated numerically using a two-way diffusion model that accounts both for monomer and short polymer chains diffusion. The concentration and spatial distribution dynamics of monomer, short and long polymer chains are calculated. It is assumed that the surface profile is a linear combination of monomer and polymer concentration with appropriate coefficients accounting for polymer shrinkage. A good agreement between the calculated and the experimentally measured profiles is observed thus demonstrating the successful application of the two way diffusion in modeling this system.


Optical Properties Of Silica-Mfi Doped Acrylamide-Based Photopolymer, Tzvetanka Babeva, Rosen Todorov, Svetlana Mintova, Temenujka Yovcheva, Izabela Naydenova, Vincent Toal Jan 2009

Optical Properties Of Silica-Mfi Doped Acrylamide-Based Photopolymer, Tzvetanka Babeva, Rosen Todorov, Svetlana Mintova, Temenujka Yovcheva, Izabela Naydenova, Vincent Toal

Articles

The optical properties of acrylamide-based photopolymer doped with pure silica MFI-type zeolites are studied by refractometric and spectrophotometric means. Dynamic Light Scattering and Transmission Electron Microscopy are used for zeolite characterization and laser refractometry and White Light Interferometric profilometry are used for surface characterization of the composites. Refractive indices and absorption coefficients of composites are determined from their transmittance and reflectance spectra. The calculated dispersion curves are further used for deriving the zeolites refractive index and porosity and the latter compared to the values of total pore volume obtained from N2-sorption measurements. The impact of the doping level on the …


Holographic Recording In Acrylamide Photopolymers: Thickness Limitations, Mohammad Mahmud, Izabela Naydenova, Nitesh Pandey, Tzvetanka Babeva, Raghavendra Jallapuram, Suzanne Martin, Vincent Toal Jan 2009

Holographic Recording In Acrylamide Photopolymers: Thickness Limitations, Mohammad Mahmud, Izabela Naydenova, Nitesh Pandey, Tzvetanka Babeva, Raghavendra Jallapuram, Suzanne Martin, Vincent Toal

Articles

Holographic recording in thick photopolymer layers is important for application in holographic data storage, volume holographic filters and correlators. Here, the characteristics of acrylamidebased photopolymer layers having thickness from 250 μm to 1-mm were studied. For each layer thickness samples with three different values of absorbance were studied. By measuring both the first order diffraction efficiency growth of holographically recorded gratings and studying the diffraction patterns obtained, the influence of scattering on the diffraction efficiency of thick volume holographic gratings was analyzed. It was observed that above a particular thickness and absorbance, the first order diffraction efficiency significantly decreased because …


Optical Properties Of Charged Polymer With Nano-Sized Zeolite Inclusions, Temenujka Yovcheva, Izabela Naydenova, Ivanka Vlaeva, Rosen Todorov, Vincent Toal, Simeon Sainov Jan 2009

Optical Properties Of Charged Polymer With Nano-Sized Zeolite Inclusions, Temenujka Yovcheva, Izabela Naydenova, Ivanka Vlaeva, Rosen Todorov, Vincent Toal, Simeon Sainov

Conference Papers

The optical characteristics of photopolymer films doped with nanoparticles are studied. The investigated systems consist of a soft polymer matrix containing porous zeolite nanoparticles with concentrations varied in the range from 0wt.% to 7wt.%. 40μm thick layers are obtained by casting the photopolymer nanocomposite solution on glass substrates. The corona charging influence on the transmission spectra and on the surface and the effective refractive index of the dry layers is investigated.


Recent And Emerging Applications Of Holographic Photopolymers And Nanocomposites, Izabela Naydenova, Pavani Kotakonda, Raghavendra Jallapuram, Tsvetanka Babeva, Denis Bade, Suzanne Martin, Vincent Toal, Svetlana Mintova Jan 2009

Recent And Emerging Applications Of Holographic Photopolymers And Nanocomposites, Izabela Naydenova, Pavani Kotakonda, Raghavendra Jallapuram, Tsvetanka Babeva, Denis Bade, Suzanne Martin, Vincent Toal, Svetlana Mintova

Conference Papers

Sensing applications of holograms may be based on effects such as change in the spacing of the recorded fringes in a holographic diffraction grating in the presence of an analyte so that the direction of the diffracted laser light changes, or, in the case of a white light reflection grating, the wavelength of the diffracted light changes. An example is a reflection grating which swells in the presence of atmospheric moisture to indicate relative humidity by a change is the colour of the diffracted light. These devices make use of the photopolymer’s ability to absorb moisture. In a more versatile …