Control of the IR-spectral shift via modification of the surface relief between the liquid crystal matrixes doped with the lanthanide nanoparticles and the solid substrate

Advances in Material Nanosensitization: Refractive Property Changes as the Main Parameter to Indicate Organic Material Physical-Chemical Feature Improvements

In the current paper, the results of the sensitization process’ influence on the refractive organic materials’ features are shown. The correlation between the refractive properties and the intermolecular charge transfer effect of doped organic thin films are shown via estimation of the laser-induced change in the refractive index. The refractive parameter is shown for a model organics matrix based on a polyimide doped with fullerenes, carbon nanotubes, reduced graphene oxides, etc. A second harmonic of the Nd-laser was used to record the holographic gratings in the Raman–Nath diffraction conditions at different spatial frequencies. The laser-induced refractive index change was considered to be an indicator in order to estimate the basic organic materials’ physical–chemical characteristics. Additional data are presented for the liquid crystal cells doped with nanoparticles. The correlation between the content of the nanoobjects in the organics’ bodies and the contact angle at the thin film surfaces is shown. Some propose to use this effect for general optoelectronics, for the optical limiting process, and for display application.

Influence of Surface Relief on Orientation of Nematic Liquid Crystals: Polyimide Doped with WS2 Nanotubes

Among the different methods for orienting liquid crystal (LC) molecules, adding nanoparticles into the matrix of the substrate material towards modifying its surface, is actively pursued. In this context, the influence of the nanoparticle content on the texture of the surface of polymer film used as the substrate for the LC orientation is of particular interest. Thus, in the current paper, WS2 nanotubes were used to dope the polyimide (PI) substrate-film in order to modify and control its surface morphology/roughness and properties. The modified organic surface structure is applied in order to achieve a new means for controlling the orientation of the LC molecules. This tool adds to the classical methods for controlling the orientation of the LC molecules, such as the display technique.

Er3+-Ions-Doped Multiscale Nanoprobes for Fluorescence Imaging in Cellular and Living Mice

With the development of biotechnology, luminescent nanoprobes for biological disease detection are widely used. However, the further application in clinic is limited by the reduced penetration depth in the tissues and light scattering. In this work, we have synthesized NaYF4:Yb,Er,Ce@SiO2-OAlg nanomaterials, which have both upconversion and near-infrared (NIR) luminescence. The optimized probes were determined to achieve cell imaging by its upconversion (UCL) luminescence and in vivo imaging through collection of NIR fluorescence signals simultaneously. The research is conducive to developing accurate diagnostic techniques based on UCL and NIR fluorescence imaging by a single nanoparticle.

ITO conducting coatings properties improvement via nanotechnology approach

In this paper the investigation devoted to study and development of the optimized ITO conducting layers are presented and discussed under the conditions of the materials surfaces laser structuration in order to apply the modified conducting materials in the optoelectronics, virus protection, solar energy, microscopy, biomedicine, etc. area. Based on our knowledge and expertise it is established the dramatic change of the main characteristics of the ITO matrix, which surface is modified by the carbon nanotubes (CNTs), and additionally treated by surface electromagnetic waves (SEW) as well. The transmittance and reflection spectral change, increase of the micro hardness and laser strength as well as the increase of the wetting angle and refraction change are discussed due to the covalent bonding between the carbon nanotubes and the near-surface atoms of the matrix materials. As the unique point of the study the effective decrease of the resistivity is established and presented. Quantum chemical simulations are supported the data presented.

Advantages of the Surface Structuration of KBr Materials for Spectrometry and Sensors

A potassium bromide (KBr) material, which has been widely used as the key element in Fourier spectrometers and as the output window of the IR-lasers, was studied via applying carbon nanotubes in order to modify the potassium bromide surface. The laser-oriented deposition method was used to place the carbon nanotubes at the matrix material surface in the vertical position at different electric fields varying from 100 to 600 V × cm^-1. The main idea of the improvement of the spectral properties of the potassium bromide structure is connected with the fact that the refractive index of the carbon nanotubes is substantially less than the refractive index of the studied material, and the small diameter of the carbon nanotubes allows one to embed these nano-objects in the voids of the lattice of the model matrix systems. Moreover, the mechanical characteristics and wetting features of potassium bromide structures have been investigated under the condition mentioned above. Analytical and quantum-chemical simulations have supported the experimental results.

Colloidal nanophotonics: the emerging technology platform

Dating back to decades or even centuries ago, colloidal nanophotonics during the last ten years rapidly extends towards light emitting devices, lasers, sensors and photonic circuitry to manifest itself as an emerging technology platform rather than an entirely academic research field.