Photorefractive Hybrid Materials Based on Inorganic Nano-Crystals Embedded in an Amorphous Organic Host

• Applicant: Professor Dr. Klaus Meerholz
• Subject Area: Experimental and Theoretical Physics of Polymers
• Term: from 2004 to 2010
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5439812

The goal of the project is to fabricate, to investigate, and to optimise a new class of hybrid materials consisting of inorganic photorefractive nano-crystals embedded into an amorphous matrix of a functional polymer. Large electric fields build up in nano-crystals under illumination because of, e.g., the bulk photovoltaic effect. These fields penetrate into the polymer host and change the refractive index owing to, e.g., the quadratic electro-optic effect, which can be enhanced by orientation of polar molecules in the nano-crystal fields. Thus after optimisation the material has the potential to show superior photorefractive properties. Nano-crystals may exhibit new physical effects owing to their sub-wavelength dimensions that result especially from surface impacts. E.g. absorption and the bulk photovoltaic coefficient can be affected. For optimisation of spectral response, recording time as well as magnitude and life-time of the induced index changes, many combinations of nano-crystals and polymers will be studied. Full experimental characterisations and theoretical desriptions are targeted (effects in nano-crystals, interaction of nano-crystals with polymers, light scattering, overall photosensitivity and optical nonlinearities).

• DFG Programme: Research Grants
• International Connection: Russia
• Participating Person: Professor Dr. Boris Sturman