This PDF file contains the front matter associated with SPIE Proceedings Volume 6732, including the Title Page, Copyright information, Table of Contents, Introduction (if any), and the Conference Committee listing.

A new method of plasma-chemical synthesis with activation of initial substances by an optical pulsating discharge in high-velocity gas flows is used for the first time to synthesize nanostructured coatings from carbon or silicon carbonitride compounds, synthesize carbon nanoparticles, and for nanostructured modification of the iron surface. Record injection rate (for plasma-chemical methods) of energy into the gas volume (>10⁹ W/cm³), high cooling rate (~10¹⁰ K/s), and the possibility of obtaining equilibrium plasma with a temperature of up to 20-30 kK open up wide possibilities for the development of effective laser-plasma nanotechnologies.

A continuum model based on a drift-diffusion approach is applied to describe the dynamics of electronic excitation, heating and charge-carrier transport in metals and dielectrics under near-infrared femtosecond laser irradiation. The dependence of laser-induced charging of the targets on laser fluence and pulse duration is investigated. Various aspects concerning the mechanism of Coulomb Explosion (CE) are discussed. The CE threshold as a function of pulse duration is evaluated numerically for dielectric materials (sapphire and ULE glass). A special attention is paid to studies of interconnection between the electron emission yield and surface charging dynamics. It has been found that in dielectrics the photoemission yield saturates with increasing laser fluence as a result of self-regulation of the free-electron population. By contrast in metals, due to effective supply of electrons to the charging zone on the target surface, electron emission becomes unwarrantably high for short laser pulses and high fluences. However, photo- and thermionic emissions can be suppressed by the generated electric field whose amplitude is a function of pulse duration and laser fluence. The question on self-consistency of electron emission and surface charging is analyzed with outlining further studies.

Research of an opportunity of formation of nanostructures on a surface of the graphite samples is now one of most actively developing directions of laser physics [1-4]. Development of the given branch is connected by that properties formed nanostructures essentially depend on parameters of laser radiation (length of a wave, duration of a pulse, the form of a beam), the laser systems developed recently allow to capture the big range of the given parameters that allows to expect for generation nanostructures with the set properties. In the given work as object of research it was used glass carbon (GC). Because of the amorphous structure, the given material rather easily gives in to action of laser radiation with density of power not exceeding 10⁷ W/sm². The specified range of intensity now is distributed enough in technological laser systems. In the carried out experiments dependences of morphological properties generated nanostructures from distance to the center of area of action are found out. It is shown, that mechanisms of their formation have the various nature. Attributes of formation of melt in the center of a laser cavity and precipitated layer from a gas phase behind borders of area of action are fixed.

We demonstrate three - dimensional (3D) structuring of materials by femtosecond laser irradiation. The self-organized ordered formation of ripples by a laser raster-scanning on the surface of 4H-SiC is demonstrated. This method is scalable up to areas with sum-millimeter cross-sections. The role of ripple-like structures in the case of the surface and in-bulk micro-structuring of different materials is discussed. The field enhancement effects at the nano-structured surfaces and their role in ripple formation are estimated.

The fast growing market of organic electronics, including organic light-emitting devices (OLED), Solar cells and radio-frequency identification devices (RFID), stimulates development of versatile technologies for patterning the thin-film materials on rigid and flexible substrates. Thin films of the transparent conducting oxides (TCO) are important materials for making transparent contacts, conductors or antennas in such devices. High repetition rate lasers with a short, picosecond pulse duration offer new possibilities for high efficiency structuring of transparent conductors on glass and other substrates. The results of ablation of the indium-tin oxide (ITO) layer on glass and ITO and ZnO layers on polymers with picosecond lasers at various wavelengths are presented. Laser radiation initiated ablation of the material, forming trenches in TCO. UV radiation at the 266 nm provided the widest working window for TCO ablation without damage of the substrate. Subcomponents of the thin-film devices were made in order to test the structuring technology.

The geometric-optical mechanism of wavefront reconstruction differs significantly from conventional holographic reconstruction. This regime can be realized for holograms containing only few periods of interference fringe structure. The geometric-optical reconstruction of the holograms recorded by femtosecond laser pulses in volume media was demonstrated in our previous works. The large thickness of the recording medium required for the effect observation is a serious obstacle for future development in this direction. In this work a way to surmount this obstacle by realizing the waveguide analog of the geometric-optical reconstruction process is presented. Holograms were recorded by 30-femtosecond laser pulses in 20-μm film of dichromated gelatin on the polished quartz substrate and reconstructed by the waveguide mode. Geometric-optical regime of waveguide hologram reconstruction was obtained: the direction of the reconstructed beam was observed to be constant as the reconstructing wavelength was varied within the hologram spectral selectivity band. The possibility of producing achromatic waveguide optical elements containing only few periods is discussed. The utilization of FIB (focused ion beam) nanotechnology for fabrication of these optical elements is proposed. Production of high aspect ratio periodic structures by FIB technology is demonstrated.

Zinc oxide nanoparticles were synthesized by pulsed laser ablation technique in water with further deposition on the single-crystalline silicon substrate. The composition, morphology, absorbance and luminescent properties of the formed structures were studied. The study revealed that films of high structural and optical quality can be prepared by the developed method.

A theoretical study of cluster formation in the plume produced by nanosecond laser pulses of moderate intensity in vacuum is undertaken on the basis of the Smoluchowski rate equations. Dynamics of the laser-induced plume expansion is described in a spherical approximation, taking into account ionization/recombination kinetics, the heat release to the plasma flow due to condensation and three-body recombination, and the vibrational relaxation of clusters. As a model system, carbon cluster formation in the plume during pulsed laser ablation of graphite has been studied. The C_n particles with n = 1-100 are considered with allowance for the isomers (chains, rings, fullerenes). The cluster collision cross sections are evaluated from the experimental data. Calculations with various initial compositions of the vaporized material (different ratios of atoms, dimers and trimers) have shown a strong impact of this factor on the expansion and ionization dynamics of the plume. The obtained results on the cluster size distribution and impact of the cluster internal degrees of freedom on the cluster growth process are analyzed in comparison with available experimental data.

Direct Laser Manufacturing (DLM) with coaxial powder injection (TRUMPF DMD 505 installation) was applied for fabrication of 3D objects from metallic and ceramic powder. One of the advantages of DLM is the possibility to build functionally graded objects in one-step manufacturing cycle by application of a 2-channel powder feeder. Several models with different types of material gradients (smooth, sharp, periodic) and multi-layered structures were manufactured from SS, stellite (Cobalt alloy), Cu and W alloys. Technology of Selective Laser Melting (SLM) was applied for manufacturing of net shaped objects from different powders (PHENIX PM-100 machine) : Inox 904L, Ni625, Cu/Sn, W and Zr02-Y2O3. Performance and limitations of SLM technology for fabrication of elements for chemical and mechanical industries are analysed. Two-component objects (Stainless steel /Cu - H13/CuNi) were fabricated in a two-step manufacturing cycle.

Results are presented from experimental and theoretical studies of current, dose and energy characteristics of ion beams in the process of ion implantation from pulsed laser plasma containing multicharged ions in an external accelerating electric field. Physical processes in expanding laser-produced plasma are simulated by the particle-in-cell method. The model predicts energy spectra of implanted ions depending on the operation conditions. It has been found both experimentally and theoretically that the current characteristics of the laser plasma expanding from the target to the substrate depend substantially on the time at which the high-voltage accelerating pulse is applied. It is established, that for an effective utilization of double-charged ions in the implantation process it is necessary to realize fast enough turning-on of an external electric field after the laser action on the target. The initiation of high voltage pulse with 50 kV amplitude 0.5 μs after the laser pulse allows realizing the implantation of ions with energy near the 100 keV level. Comparison of experimental and calculated depth distributions shows that the developed model quite adequately describes formation of high-energy components of ion beam which provides the defect formation and alloying of the deep layers of the substrate.

Enhancing the diffraction efficiency for direct laser writing of continuous-relief diffractive optical elements (DOEs) is discussed. An influence of laser beam positioning errors on the diffraction efficiency has been investigated. Optimization of exposure data set permits to decrease negative effects related to positioning errors and with convolution of a desired phase profile with writing beam intensity distribution. New methods (zone boundary optimization and optimized double writing) with exposure optimization near diffractive zone boundaries have been proposed and compared with known ones.

experimental and numerical investigations of laser annealing of thin ferroelectric heterostructures have been presented in this paper. Laser annealing of thin films has been made in KrF laser facilities (Lebedev Phys. Institute, Moscow). 2D numerical code "TEPOL" have been developed for modeling of physical processes in multilayer samples. X-ray structural analysis and e-beam microscopy have been used to research the samples. The laser heating leads to partial crystallization of film and considerable change metal system in compare with traditional heat treating. A new approach to the study of samples with help of photo-acoustic method has been discussed in the paper.

Photoluminescence of CdSe/ZnS quantum dots may be orders of magnitude enhanced varying geometry and polarization of excitation and sizes and shapes of their self-assembled units. We show that this effect is accompanied by dramatic decrease of quantum dots mean photoluminescence life times and propose a roadmap for creation of nanosructures with advanced optical properties.

Precision laser-writing systems operated in polar coordinates and direct writing technologies for fabrication of diffractive optical elements and computer generated holograms have been described. These systems can manufacture continuous-relief and binary microstructures with minimum feature sizes of less than 0.6 μm and laser beam positioning accuracy of 0.05 μm over 300-mm substrates. Hardware and software of the system permit to write on different types of photosensitive and thermal recording materials. Several examples of fabricated diffractive elements have been presented.

The new express method of the direct spectrochemical analysis of solid materials is proposed on the basis of laser ablation of a sample in deionized water with on-line transportation of a suspension in analytical volume of inductively-coupled plasma of optical emission spectrometer. In result, all instrumentation and methodical advantages of the standard equipment in a combination with calibration procedure by standard water solutions are provided.

Formation of nano-fibers ranging from 30 to 300 nm in diameter and exceeding the length of one millimeter was observed during explosive ablation of As₂S₃ glass by femtosecond pulses at high fluence (> 5 J/cm²) irradiation of the 800 nm wavelength, 160 fs duration pulses in air. However, the spheres of up to several microns in diameter are found to form competing with nano-fiber formation and significantly deteriorating their morphology. The formation of these spheres is explained by the free energy minimization of explosively ablating liquid jets combined with the onset and evolution of the thermo-capillary forces at the local perturbations of the geometry and temperature. Performed thermal analysis suggests that the good nano-fiber morphology can be preserved by increasing the air pressure or ablation in water which shortens the characteristic cooling and solidification time of the liquid jets, and inhibits the development of the small geometrical perturbations into the large spheres.

Simulations of optical radiation transformation by spherical microparticles containing monomers of nanoparticles inside or on the surface of them have been performed. Conditions of microparticle internal field variations are obtained under changes of monomer concentration.

MoSe_x coatings were obtained by pulsed laser deposition in vacuum and inert Ar gas atmosphere at the pressure from 1 to 10 Pa. The deposition temperature was 200°C. The films were studied by means of X-ray diffraction, scanning and transmission electron spectroscopy, X-ray photoelectron spectroscopy, Rutherford backscattering spectroscopy of helium ions. The tribological properties of thin film coatings were investigated by pin-on-disk testing in air with 50% relative humidity. Chemical composition, structure, and tribological properties of the coatings were found to be sensitive to the presence of the inert gas. Thus, increasing the gas pressure from 1 to 10 Pa changes the chemical composition, so that the value of x increases from 1.5 to 2.4 in the principal deposition zone. At the optimal gas pressure (~ 2 Pa), the composition of the coating was close to the stoichiometric one, and the layer adjacent to the substrate consisted of MoSe_x nano-crystals with the basal planes parallel to the substrate surface or oriented at small angles to the surface. The tribological properties of MoSex coatings deposited on steel substrates depend on the gas pressure. The friction coefficient in air decreases from 0.08 for deposition in vacuum to 0.04 for deposition at the optimal pressure.

It is described the express optical method of evaluation of thin-film coatings, deposited on metal or semiconductor surface. For the tested samples of enamel-covered duralumin it is found the linear dependence of maximal intensity and half-width of secondary radiation on the thickness of the coating.

Kinetics of polymer microelements growing on the top of optical fiber with use of different photoactive additives (Rodamine B, Coumarin) was studied. Consequently, the technological principles of production of polymer self-adjoint microelements were founded

The electron beam irradiation effect on optical characteristics of polystyrene films modified by carbon nanoparticles is investigated. It was found that reflectance and transmittance of films modified by nanotubes, are in some times less, than corresponding reflectance and transmittance of polystyrene films without additives or films, modified by C₆₀. The electron irradiation of samples modified by nanoparticles results to the decreasing of depolarization degree of laser radiation reflected and transmitted by investigated films.

By means of goniophotometric Stokes polarimeter angular distribution of polarization characteristics of He-Ne laser radiation reflected by polyvinyl alcohol (PVA) films modified with SiO₂ nanosol was investigated. Increasing of nanosol content in PVA films caused increasing of intensity of diffuse component and decreasing of polarization degree of radiation reflected at the angles from 20° to 60-70°.

The main goal of the work was optimization of the phase and porous fine structures of filter elements and subsequent laser synthesis by the method layer-by-layer Selective Laser Sintering (SLS) of functional devices, exploration of their properties and requirements of synthesis. Common methodical approaches are developed by the searching optimal requirements of layer-by-layer synthesis usable to different powder compositions and concrete guidelines (conditions of sintering, powder composition, etc.) for SLS of filter elements (including anisotropic) from metal-polymer powder mixture - brass + polycarbonate{PC} = 6:1. As a result of numerical simulations it designed an original graph - numerical procedure and represented a computer program for definition of flow filter performances, as homogeneous (isotropic) as heterogeneous (anisotropic), having the cylindrical shape. Calculation of flow behavior for anisotropic filter elements allows predicting their future applications and managing its.

In now time the schemes with using action on an initial sample in vacuum or buffer gases to obtaining nanostructures and nanoclusters during laser ablation is applied [1-4]. The main reason of using these schemes is reaction of burning of carbon in atmospheric air. In the given work studying of precipitation of evaporated carbon on a surface of a cold substrate are carried out at action of radiation of the YAG:Nd-laser in atmospheric air. The samples from carbons materials with various density and a degree of order are irradiated. Surfaces of substrates after laser action are investigated with use scanning probe microscope Smena-B. Formations nanostructures are fixed. The dependence of properties of obtained structures from type of irradiated material and conditions of experiment (duration of a pulse, duration of action, distance between a sample and a substrate) is determined.

A numerical simulation of the dynamics of melting and crystallization processes induced in cadmium selenide by radiation of the KrF excimer laser (&lgr; = 248 nm, &tgr; = 20 ns) was carried out taking into account the components evaporation from the surface and their diffusion in the melt. It is shown that intensive components evaporation from the surface results in the formation of nonmonotone temperature profile with maximum temperature at a depth of about 5 - 15 nm. As a result, melt formed in the semiconductor volume extends both to the surface and to the depth of sample. After termination of the laser radiation enrichment of the surficial region by selenium is equals ~ 0.51.

We present a new microtechnology of hole drilling based on Nd:YAG laser with self-adaptive loop resonator and scanned passive LiF:F₂^- Q-switch. It allowed us to provide a high-productive laser drilling of 100-micron holes deeper than 10 mm at average drilling rate higher then one micron per laser pulse.

The laser trapping and manipulation by submillimeter size absorbing particles in the laser tweezer is investigated. The stable levitation of graphite, magnetite, tungsten carbide solid particles and its conglomerates was performed in laser trap formed by hollow laser beam focused by long-focal objective. The particles dynamics in the trap at normal and lowered air pressures was studied. The some new applications of laser tweezers with absorbing particles are discussed

The solgel process successfully prepared Nd₂O₃ / SiO₂ nanocomposites. After drying in air at 85°C for three days, samples were heat treated, in air, at 750, 950, 1150 and 1250°C. Characterizations were made by, Infrared spectroscopy, X-ray diffraction, and scanning electron microscopy. Mechanisms of neodymium oxide nano clusters formation in the densified silica matrix with respect to thermal treatment are discussed. XRD profiles confirm the crystallinity of the nanoclusters. The size of the nanoclusters was found in the range 15-30nm.

The idea of antireflective grating transmitting incident light into diffracted orders is presented. Possible design of such a grating for devices operating at 1.06 mkm was developed using effective medium theory (EMT). The diffraction efficiency was rigorously calculated and compared with EMT predictions. The possibility of proposed grating to combine an interference mechanism of light reflection reduction and diffractive mechanism of light redirection is shown.

The work presents the determination of the laser-induced damage threshold (LIDT) fluence of sapphire under various experimental conditions concerning the material irradiation (fs, ps and ns temporal regimes) and material preparation (surface state). The results may be used for optimising laser micromachining processes and also for studying laser crystal damage in high peak power femtosecond Ti:Sapphire laser chains.

The thin films of zinc oxide have been produced at various levels of doping with gallium. The dependence of the ZnO film crystallographic parameters on the deposition process parameters has been established. The dependence of the photoluminescence spectra of films on the conditions of deposition has been investigated. A study has been made of the intensity, emission band width, and the value of Stokes shift of ZnO films.

A simple and effective method of computer simulation of inorganic photoresist based on chalcogenide glass As₂S₃ development is proposed. The photoresist is exposed by interference photolithography, which is a promising technology for large-scale producing of subwavelength surface relief grating. The influence of exposure and photoresist parameters was investigated in order to produce periodical structure with a period of almost half of exposing wavelength.

The method of processing and on-line holographic control on the basis of the single laser system is offered. Material processing and control for the progress of work are realized with the same Nd:YAG-laser. The method is based on utilizing the basic wavelength (λ₁=1.064 μm) millisecond pulse for processing purpose and the second harmonic (λ₂=0.532 μm) that of nanosecond width for holographic recording on photothermoplastic medium.

With the help of laser method the metal nanoparticle susupensions (Ag, Zn, V) and diamond carbon films were formed. The effective size of metal nanoparticles in liquid media was defined due to the method of laser probing. The optical properties (transmission, index of refraction) of diamond carbon films and metal nanoparticle susupensions (absorption) were investigated. The dependence of carbon films thicknesses on deposition condisions were obtained.