Pulse laser deposition technique was used to deposite (Ag3AsS3)0.6(As2S3)0.4 thin films upon previously prepared gold nanoparticle layers. The optical transmission spectra of sandwich structure based on Ag3AsS3)0.6(As2S3)0.4 thin film and gold nanoparticles were studied in the temperature range 77-300 K. Temperature behaviour of the Urbach absorption edge as well as the temperature dependences of the energy pseudogap and Urbach energy were investigated. The effect of the order-disorder processes on the optical properties of sandwich structure was discussed. Optical parameters of Ag3AsS3)0.6(As2S3)0.4 thin film and sandwich structure based on (Ag3AsS3)0.6(As2S3)0.4 thin film and gold nanoparticles were compared.
Our investigations relate to the development of new polymer nanocomposite materials and technologies for fabrication of photonic elements like gratings, integrated elements, photonic crystals. The goal of the present work was the development and application of the multi-beam interference method for one step, direct formation of 1-, 2- or even 3D photonic structures in functional acrylate nanocomposites, which contain SiO2 and Au nanoparticles and which are sensitized to blue and green laser illumination. The presence of gold nanoparticles and possibility to excite plasmonic effects can essentially influence the polymerization processes and the spatial redistribution of nanoparticles in the nanocomposite during the recording. This way surface and volume phase reliefs can be recorded. It is essential, that no additional treatments of the material after the recording are necessary and the elements possess high transparency, are stable after some relaxation time. New functionalities can be provided to the recorded structures if luminescent materials are added to such materials.
(Ag3AsS3)0.3(As2S3)0.7 thin films were deposited onto a quartz substrate by rapid thermal evaporation. The optical transmission spectra of thin films were measured in the temperature range 77–300 K. It is shown that the absorption edge spectra are described by the Urbach rule. The temperature behaviour of absorption spectra was studied, the temperature dependences of energy position of absorption edge and Urbach energy were investigated. The influence of transition from three-dimensional glass to the two-dimensional thin film as well as influence of Ag3AsS3 introduction into As2S3 on the optical parameters of (Ag3AsS3)0.3(As2S3)0.7 were analysed. The spectral and temperature behaviour or refractive index for (Ag3AsS3)0.3(As2S3)0.7 thin film were studied.
Homogeneous, 200 – 3000 nm thick layers of chalcogenide glasses, 1 – 2 mm thick plane-parallel plates as well as nanocomposite structures, containing gold nanoparticles have been produced and used for in situ surface optical and geometrical relief fabrication by optical- or electron-, ion-beam recording. Investigations were focused on the formation of giant (height modulation from nanometers up to micrometers) geometrical reliefs and elements (dots, lines and diffractive elements) applicable in the 0.5 – 10 micrometer spectral range. Recording parameters were compared with available data on acrylic polymer nanocomposites. The mechanism of the recording processes, which include thermal, electron and mass-transport components were explained and the selection of the materials from As(Ge)-S(Se) binary systems with best recording parameters was done.
The process of holographic recording based on a direct formation of periodic surface relief in AsxSe1-x (0 ≤ x ≤ 0.5) and
As2S3 layers was investigated by in situ AFM depth profiling and compared with data on diffraction efficiency η of the
similar relief holographic gratings, measured in a reflection mode. It is established, that the time (exposure) dependence
of η has at least two components, which are connected with different components of the surface deformation Δd and
relief formation up to the giant, Δd/d >10% changes in the best As0.2Se0.8 or As2S3 compositions. Correlation is found
between light and e-beam induced surface deformations during recording in similar compositions. Applications for
prototyping phase-modulated optoelectronic elements are considered.
Investigations of interdiffusion effects in chalcogenide nanomultilayers were extended towards the
Bi(Sb)/As2S3 structures. It was shown that the interdiffusion in these nanocomposites was mainly determined by thermal effects due to the direct heating or to the influence of the intensive laser beam unlike the chalcogenide-chalcogenide nanostructures, where the photo-induced effects may dominate. Solid-phase synthesis, efficient amplitude-phase modulated optical relief recording can be performed this way.
Investigations of optical recording processes in amorphous chalcogenide layers were extended to the compositionally
modulated amorphous nanomultilayers made of different pairs of chalcogenide glasses from As-S(Se) systems or pairs
of chalcogenide glasses and metals, dielectrics. This type of recording is connected to the light-stimulated mass transport
across the interfaces, possible phase transformations and correlated changes of optical parameters (absorption, refraction,
reflection). The interconnections between the compositional modulation at nano-scale dimensions (~3-10 nm) and
possible improvement of recording parameters (the rate and degree of optical bleaching, darkening, local changes of the
thickness and of the refractive index, spatial resolution) were established.