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A method is proposed for the synthesis of linear carbon chains under irradiation of colloidal systems consisting of schungite nanoparticles by an ytterbium fibre laser with a pulse duration of 100 ns and an energy up to 1 mJ. Colloidal systems have been previously prepared by laser ablation of a schungite target in distilled water using a Nd3+ : YAG laser with a pulse duration of 1 ms and an energy up to 10 J.

We report experimental results on laser formation of carbon nanostructures produced during irradiation of a target placed in water. We have performed comparative experiments on laser heating of carbon targets by millisecond and femtosecond laser pulses. It is shown that under different conditions of laser irradiation of targets made of schungite, glassy carbon and pyrolytic graphite, different morphological types of micro- and nanostructured carbon are formed.

Laser processing of epitaxial PbSe films has been found to produce periodic concentric surface ring structures that extend over several laser spot radii from the exposed zone. The proposed theoretical interpretation of this effect in terms of defect -- deformation interactions adequately describes the observed morphology, periodicity and complex (multimode) shape of the ring structures.

We propose approaches to producing micro- and nanostructured titanium oxide surfaces via exposure to cw laser radiation and repetitive laser pulses. By varying the experimental geometry (angle of incidence, substrate-target separation and other parameters), various structures can be obtained. Titanium oxide tubes grown in a nonuniform magnetic field are up to 1 mm in diameter and up to 500 mm in length. Such structures can be used in catalytic filtration and as multiwalled structures similar to superlattices.

Abstract: The morphology of lead telluride surface films with helical formations on (111) barium fluoride substrates in the initial state and after treatment in an argon plasma is studied using atomic force microscopy. It is shown that the presence of large helical stepped structures near the outcrops of threading dislocations results in specific phenomena upon sputtering. The main features of the modification of the surface relief and the relation of the nascent single and grouped microhillocks to the initial surface relief and dislocations are determined.

The solidification morphology of carbon materials surface-melted by laser radiation at atmospheric pressure is studied. Electron microscopy results indicate that melt solidification is accompanied by the formation of surface microstructures, presumably due to the Rayleigh--Taylor instability in the molten carbon. The instability increment and surface tension coefficient of molten carbon are estimated, and the penetration of carbon vapour into the melt during one laser pulse is examined using numerical simulation.

An experimental technique for obtaining nanostructures in the field of high-power laser radiation at the surface of carbon materials is developed. A specific feature of this technique is the formation of liquid carbon inside the region of laser action in the sample exposed to radiation in air at a pressure of [?]1 atm. Several types of nanostructures (quasi-domains and nanopeaks) are detected in the laser cavern and beyond the range of laser action. Mechanisms of formation of such structures are proposed. The formation of quasi-domains is related to crystallisation of the melt. The nanopeak groups are formed outside the laser action region during the deposition of hot vapours of the material escaping from this region. The dependences of the variation in morphological properties of the nanostructures on the duration of laser action and the radii of typical cavern zones on the laser radiation power are obtained.

We report for the first time the formation of a nanoparticle ensemble on a binary semiconductor (PbTe) film under cw laser irradiation. It is shown that defect -- deformation theory of the formation of nanoparticle ensembles in the solid state under cw laser irradiation adequately describes experimental data. In particular, it predicts a bimodal nanoparticle size distribution function that agrees well with the experimental distribution function.

We report for the first time the formation of a nanoparticle ensemble on a binary semiconductor (PbTe) film under cw laser irradiation. It is shown that defect — deformation theory of the formation of nanoparticle ensembles in the solid state under cw laser irradiation adequately describes experimental data. In particular, it predicts a bimodal nanoparticle size distribution function that agrees well with the experimental distribution function.

Laser processing of epitaxial PbSe films has been found to produce periodic concentric surface ring structures that extend over several laser spot radii from the exposed zone. The proposed theoretical interpretation of this effect in terms of defect — deformation interactions adequately describes the observed morphology, periodicity and complex (multimode) shape of the ring structures.

We propose approaches to producing micro- and nanostructured titanium oxide surfaces via exposure to cw laser radiation and repetitive laser pulses. By varying the experimental geometry (angle of incidence, substrate-target separation and other parameters), various structures can be obtained. Titanium oxide tubes grown in a nonuniform magnetic field are up to 1 μm in diameter and up to 500 μm in length. Such structures can be used in catalytic filtration and as multiwalled structures similar to superlattices.

For obtain nanostructured surfaces on various materials the method of laser deposition of metals from solutions (LDMS) was used. As a solution were used nanosystems: oxide copper (CuO) and a two-component solution of nickel (Ni) and carbon nanotubes. Deposition occurred action of pulse-periodic laser radiation (a wave length 1.06 microns, a pulse length 100ns, a repetition rate of impulses 20 kHz) various power. Laser radiation was focalized on a substrate from a quartz glass and copper. Obtain samples were research on a raster-type electronic microscope (Quanta 200/3D) and an atomic-force microscope (Ntegra Aura). As a result deposition occurred only on a trajectory of a motion of a beam. Deposition layers has good adhesion to a substrate surface. <> actions of laser radiation as the substrate surface is not exposed to thermal action. The layer roughness made 270nm at height of a relief about 2 microns. The offered method of deposition of metals from the colloid solutions by means of laser radiation is simple, inexpensive, and to substrates scaled to the big areas and length of the precipitated layer.

The solidification morphology of carbon materials surface-melted by laser radiation at atmospheric pressure is studied. Electron microscopy results indicate that melt solidification is accompanied by the formation of surface microstructures, presumably due to the Rayleigh—Taylor instability in the molten carbon. The instability increment and surface tension coefficient of molten carbon are estimated, and the penetration of carbon vapour into the melt during one laser pulse is examined using numerical simulation.

An experimental method is developed for preparing nanostructures in the field of high-power laser radiation (∼107W cm-2) upon deposition of vapours of carbon-containing materials on a cold substrate surface. A specific feature of the method is irradiation of a sample in air at room temperature and pressure close to 1 atm. The dependences of the morphologic properties of nanostructures on the distance between a substrate and a sample are determined. Variations in the size of deposited nanostructures and their characteristic shape depending on the chosen material are found.

An experimental technique for obtaining nanostructures in the field of high-power laser radiation at the surface of carbon materials is developed. A specific feature of this technique is the formation of liquid carbon inside the region of laser action in the sample exposed to radiation in air at a pressure of ≈1 atm. Several types of nanostructures (quasi-domains and nanopeaks) are detected in the laser cavern and beyond the range of laser action. Mechanisms of formation of such structures are proposed. The formation of quasi-domains is related to crystallisation of the melt. The nanopeak groups are formed outside the laser action region during the deposition of hot vapours of the material escaping from this region. The dependences of the variation in morphological properties of the nanostructures on the duration of laser action and the radii of typical cavern zones on the laser radiation power are obtained.