Nanocomposites based on transparent polymer matrices containing nanoparticles (NPs) of noble metals are modern-day materials that can be specially designed for photonics, linear and nonlinear optics, laser physics and sensing applications. We present the improved photosensitive nanocomposites doped with Au and Ag NPs allowing fabrication of high effective submicrometer dimensional diffraction structures using holographic method. A general approach for the fabrication of holographic structures using a two-component mixture of the monomers of different reactivity was developed. Two different methods, ex situ and in situ, were studied to introduce Au and Ag NPs in the polymer matrix. The diffusion model of the grating formation upon holographic exposure as well as the process of Ag NP synthesis in a polymer matrix is considered. The influence of the NP size on the polymerization process, material dynamic range and nonlinear properties were investigated. The mechanisms and characteristics of the nanocomposite nonlinear optical response are discussed.

The photorefractive characteristics of Ti-doped CdTe semi-insulating crystals were measured. Additional optical and photoelectric measurement confirmed that titanium has advantages over other dopants and that this material has better characteristics for potential applications. The high optical holographic gain coefficient, Γ≈0.60 cm−1, low background absorption, kb≈0.2 cm−1, high optical quality and homogeneity, and almost monopolar (electronic) photoconductivity show that these materials can be effectively used for both optical and photoelectric applications in the near infrared region. Studies of the optical absorption and photodiffusion current made it possible to determine the nature and energy structure of impurity and intrinsic defects as well as to establish their role in the photorefractive effect. It is shown that the excited impurity T14(F) state is in resonance with the conduction band. As a result, autoionization of electrons to the conduction band under laser excitation takes place. An energy-level diagram, both of impurity and intrinsic defects, in the CdTe:Ti crystals was constructed.

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