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The influence of various modes of ultrasonic impact treatment on the surface quality in Ti-6Al-4V samples manufactured by 3D laser printing was studied. The effect of the technological parameters of the ultrasonic setup, like power of the ultrasonic generator and indenter speed, on the surface structure and properties was defined. Based on the analysis of the microstructure, microhardness, and surface roughness of the Ti-6Al-4V sample manufactured by 3D laser printing, the optimal regime of ultrasonic treatment providing homogeneous surface microstructure and good mechanical properties of 3D laser printed samples was found. [ABSTRACT FROM AUTHOR]

This study provides a summary of latest solar cell results achieved with parallel dispensing equipment that will be commercialized by a Fraunhofer ISE spin-off (HighLine Technology GmbH) within the next year. The goal was to show alternative process routes for the PV back-end, some of them without any laser or screen printing steps involved. On the front surface of conventional PERC solar cells, an efficiency of ղmax = 21.9% was reached applying 150 parallel dispensed contacts with a finger width of only wf = 17μm but still excellent contacting behavior. Successful applications of fire through Al pastes were demonstrated on bifacial p-PERC and n-PERT samplings. On the latter, the Voc gap to a dispensed AgAl reference was only ΔVoc = -1.7mV which shows that a potential replacement of Ag by Al is possible once a better conductivity of Al-FT pastes is achieved. On HJT solar cells, dispensed Ag and AgCu contacts were demonstrated by applying commercial available low temperature screen printing pastes with the former outperforming the screen printed reference by Δղ = +0.3%abs reaching ղmax = 22.2% at a substantial decrease of Ag paste laydown. [ABSTRACT FROM AUTHOR]

The article presents the research results of the material structure intended to replace defects in biological tissues. The material is a three-layer composite obtained from aqueous dispersions of organic components - albumin, collagen and chitosan succinate, connected to a formed inorganic porous matrix, obtained under the influence of radiation from an ytterbium laser with a wavelength of 1064 nm on single-wall carbon nanotubes. To study the binding of the material components to the carbon matrix, the morphology of the resulting layers and the structural parameters of the composite scaffold the methods of vibrational spectroscopy (infrared spectroscopy and Raman spectroscopy), confocal microscopy and SEM were used. It has been established that during the action of laser radiation on aqueous dispersions there is no destruction of the organic components structure. The SEM study indicates the presence on the sample surface of globules with a size of 10-50 microns, formed from nanotubes with matrix materials. The presence of pores in the composite scaffold and their dimensions suggest the possible precipitation and proliferation of the cellular component. [ABSTRACT FROM AUTHOR]

Photothermal boiling in nanofluids is an energy-efficient process finding multiple promising applications in medicine, space technology, laser printing and nuclear engineering. The most important field is though solar energy where the nanoparticle-driven boiling of the base fluid drives a nano-turbine or a distillator. Hundreds of experimental and theoretical studies has been conducted in this direction over the past decade. There is however no reliable theory that describes kinetics of the process. The present contribution presents a numerical model of the process of photo-thermal evaporation in aqueous nanofluids. The model was used to predict the evaporation rate depending on concentration of the nanoparticles. The simulation results were compared with the experimental data over a range of concentrations (up to 10% wt.), demonstrating suitable agreement with the experiment. [ABSTRACT FROM AUTHOR]

Pulsed-laser fabrication of noble-metal nanorings with a tunable internal porous structure, which can be further uncapped by using an ion-beam etching procedure, was demonstrated for the first time. Density and average size of the pores were shown to be tuned in a wide range by varying an applied pulse energy and a chemical composition of the metal film controlled via the film magnetron deposition in the appropriate gaseous environment. According to our preliminary numerical simulations, the controlled porosity provides multifold near-field enhancement of the electromagnetic fields, making such structures promising for spectroscopic bioidentification based on a surface-enhanced Raman scattering. [ABSTRACT FROM AUTHOR]

Recently demonstrated efficient second harmonic generation in centrosymmetric silicon nanoparticles fabricated by an optimized laser printing technique is attributed to nanocrystalline structure of nanoparticles supporting the Mie resonances. Here we demonstrate that second harmonic from such nanoparticles can be generated and split as much as 14 meV at room temperature under femtosecond IR pulses revealing new functionalities of modern nanophotonics elements - all-dielectric nanoparticles. [ABSTRACT FROM AUTHOR]

This paper presents a Pulsed-Laser Printing process applied to silver nanoparticles ink with different viscosity properties with the goal to print conductive lines on various substrates. The Laser-Induced Forward Transfer (LIFT) technique has been used as a spatially-resolved laser deposition method. All materials have been transferred from a donor substrate onto a receiver substrate upon laser pulses in the picosecond regime. The efficiency of the LIFT confirms the significant potential of a laser direct-printing technique in the development of plastic microelectronics. [ABSTRACT FROM AUTHOR]

This paper presents a Pulsed-Laser Printing process applied to metals, liquid, polymers and oligomers with the goal to fabricate Organic Thin-Film Transistors. The Laser-Induced Forward Transfer (LIFT) technique has been used as a spatially-resolved laser deposition method. All materials have been transferred from a donor substrate onto a receiver substrate upon laser pulses in the picosecond regime. The broad nature of transferred patterns and the efficiency of the LIFT confirm the important potential of a laser printing technique in the development of the plastic microelectronics. [ABSTRACT FROM AUTHOR]

Laser printing technique offers an effective, fast process and free of lithography for fabricating spherical nanoparticles. on the other hand, GeSbTe (GST) compound has attracted a lot of attention in the field of reconfigurable metamaterials. Here, we use this method to fabricate the spherical GST nanoparticles. Transmission electron microscopy (TEM) analysis of the GST nanoparticles shows a broad size distribution of spherical nanoparticles which makes them resonant in wide spectral range. We also study the nonlinear optical properties of the nanoparticles demonstrating a sharp increase of second harmonic generation (SHG) at the transition point from amorphous to crystalline states. [ABSTRACT FROM AUTHOR]