Papers by Grzegorz Gawlik
Luminescent Solar Concentrators (LSCs) suitable to work in conjunction with a new type of a silic... more Luminescent Solar Concentrators (LSCs) suitable to work in conjunction with a new type of a silicon epitaxial edge-illuminated solar cell (EISC) are developed, and the operating principle of epitaxial EISCs and their specific properties are explained and discussed. The potential application of active composite materials based on luminescent nanocrystals dispersed in a polymer matrix (PMMA) in the LSCs technology is shown. The results of the synthesis of the transparent material by the incorporation of the clusters of co-doped Nd and Yb yttrium aluminum garnet Y3Al5O12 (YAG), gadolinium gallium garnet Gd3Ga5O12 (GGG) and yttrium oxide Y2O3 (YO) nanocrystals into the polymethyl methacrylate (PMMA) polymer matrix and the characterization of the synthesized materials by spectroscopic and emission dynamic studies are presented. The analyzed nanocrystals of YAG, GGG and YO compounds were prepared by the modified sol-gel method. The results indicate that the investigated materials, i.e. po...
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2020
The main aim of the work was investigation of the graphene resistance on mechanical scratch after... more The main aim of the work was investigation of the graphene resistance on mechanical scratch after ion beam bombardment. The CVD graphene on the glass substrate was used. Bombardment of graphene by beams of helium and nitrogen ions of energy 100 keV was applied. Density of ion induced defects in graphene was evaluated using Raman spectroscopy. The polymer indenter was applied for scratch test. Increase of the scratch resistance of the graphene after ion beam bombardment was observed. Scratch resistance of the graphene layer increases with increasing density of defects induced by helium and nitrogen ions. The shape of graphene ribbons exfoliated during scratch test suggests that increase of graphene scratch resistance is accompanied with improvement of graphene adhesion to the substrate. It suggests that ion beam induced defects may be responsible for observed increasing of both graphene scratch resistance ad graphene adhesion to the substrate.
Chinese Physics B, 2019
The experimental knowledge on interlayer potential of graphitic materials is summarized and compa... more The experimental knowledge on interlayer potential of graphitic materials is summarized and compared with the computational results based on phenomenological models. Besides Lennard–Jones approximation, the Mie potential is discussed, as well as the Kolmogorov–Crespy model and equation of Lebedeva et al. An agreement is found between a set of reported physical properties of graphite (layer binding energies, compressibility along c-axis in a broad pressure range, Raman frequencies for bulk shear and breathing modes under pressure), when a proper choice of model parameters is taken. It is argued that anisotropic potentials, Kolmogorov–Crespy and Lebedeva, are preferable for modeling, as they provide a better, self-consistent description. A method of fast numerical modeling, convenient for the accurate estimation of the discussed physical properties, is proposed. It may be useful in studies of other van der Waals homo/heterostructures as well.
Infrared Physics & Technology, 2019
Conductive graphene electrode of large area is required for some applications like for example ph... more Conductive graphene electrode of large area is required for some applications like for example photovoltaics or touch screens. Such large area graphene membrane needs specific test methods to assess defects which may obstacle its performance. In this work the infrared imaging of Joule heated graphene was proposed to estimate its uniformity and mechanical continuity. Thermal signatures of the typical mechanical defects like scratches and local resistivity inhomogeneity were identified. Distribution of the heat emission around such defects were simulated using finite elements method and then experimentally verified by recording of thermal landscape around the corresponding real graphene defects. Proposed method gives micrometric resolution and ability to inspection of large area electrodes depending on applied optics. Presented results give suggestions how graphene imperfections generate observed hot points related to graphene layer defects.
Nuclear Fusion, 2017
Original content from this work may be used under the terms of the Creative Commons Attribution 3... more Original content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2017
The efficiency of defect generation by atomic ions depend on ion mass and energy similarly as vac... more The efficiency of defect generation by atomic ions depend on ion mass and energy similarly as vacancy generation directly by ion predicted by SRIM simulations. However, efficiency of defect generation in graphene by molecular carbon ions is essentially higher than summarized efficiency of similar group of separate atomic carbon ions of the same energy that each carbon ion in a cluster. The evolution of the D/D 0 ratio of Raman lines intensities with ion fluence was observed. This effect may indicate evolution of defect nature from sp3-like at low fluence to a vacancy-like at high fluence. Observed ion graphene interactions suggest that the molecular ion interacts with graphene as single integrated object and should not be considered as a group of atomic ions with partial energy.
Microscopy and Microanalysis, 2013
Extended abstract of a paper presented at Microscopy and Microanalysis 2013 in Indianapolis, Indi... more Extended abstract of a paper presented at Microscopy and Microanalysis 2013 in Indianapolis, Indiana, USA, August 4 – August 8, 2013.
Acta Physica Polonica A, 2011
The aim of this work was the evaluation of ion-beam induced luminescence for the characterization... more The aim of this work was the evaluation of ion-beam induced luminescence for the characterization of luminescent oxide materials containing rare earth elements. The yttrium aluminium garnet epilayers doped with Nd, Pr, Ho, and Tm atoms were used. The ion-beam induced luminescence spectra were excited using 100 keV H + 2 ion beam and were recorded in the wavelengths ranging from 300 nm up to 1000 nm. The separate parts of the surface of the same samples were used for ion-beam induced luminescence and cathodoluminescence experiments. Cathodoluminescence spectra have been recorded in the range from 370 nm up to 850 nm at 20 keV e-beam in scanning electron microscope equipped with a grating spectrometer coupled with a photomultiplier. The observed narrow ion-beam induced luminescence lines can be ascribed to the well known radiative transitions in the rare-earth ions in the YAG crystals. The cathodoluminescence spectra reveal essentially the same emission lines as ion-beam induced luminescence. The decrease of the ion-beam induced luminescence lines intensity has been observed under the increasing ion fluences. The ion-beam induced luminescence may be used for characterization of transparent luminescent materials as an alternative method for cathodoluminescence and can be especially useful for observation of ion-beam damage formation in crystals.
Surface and Coatings Technology, 2016
Abstract Single layer graphene grown by chemical vapor deposition (CVD) method on Cu foil and the... more Abstract Single layer graphene grown by chemical vapor deposition (CVD) method on Cu foil and then transferred onto a borosilicate glass substrate was used in the experiments. The graphene samples were irradiated by singly charged ions of helium, nitrogen, argon or krypton at the energy of 100 keV up to fluence ranging from 1 × 1011 cm− 2 to 1 × 1016 cm− 2. Raman spectroscopy was used for the detection of defect size and density in graphene caused by ion irradiation. The ion induced defect size and density were determined from the Raman spectra measurements. The applicability of the SRIM code for simulation of defects generation by ions in graphene was tested. Finally, the controlled generation of the defects in graphene by using ion implantation was verified.
Physics and Chemistry of Minerals, 2016
of point defects. Both, IL and CL techniques, appear as new, complementary tools bringing new pos... more of point defects. Both, IL and CL techniques, appear as new, complementary tools bringing new possibilities in the damage accumulation studies in single-and polycrystalline materials.
Journal of Materials Science, 2000
The effect of silicon ion implantation upon the corrosion resistance and structure of the surface... more The effect of silicon ion implantation upon the corrosion resistance and structure of the surface layers formed during the implantation in the Ti6A14V titanium alloy was examined. The silicon doses were 0.5, 1.5, 3.0 and 4.5 × 1017Si+/cm2, and the ion beam energy was 100 keV. The corrosion resistance of the samples exposed to a 0.9% NaCl solution at a
Advances in Intelligent Systems and Computing, 2015
The paper presents results of Joule heating measurements in graphene samples performed in a speci... more The paper presents results of Joule heating measurements in graphene samples performed in a specially designed environmental chamber. The experimental stand was designed and described in the paper, paying particular attention to the project of the environmental chamber. The graphene samples preparation process was also discussed. Results of the testing were presented and analyzed and the conclusions are formulated, which are also included in the paper.
Advances in Intelligent Systems and Computing, 2015
The influence of the wet and warm atmosphere on CVD graphene was investigated. The CVD graphene g... more The influence of the wet and warm atmosphere on CVD graphene was investigated. The CVD graphene grown on Cu foil and then transferred onto the BK7 glass substrate was applied in the experiments. The environmental conditions were established using designed environmental chamber. The wet (RH = 80%) and warm (T = 32 oC) atmospheres were applied for up to eight hours every day for nine days experiment. Rest of time the sample was stored in room conditions. The small changes of the graphene resistance were observed during experiment. SEM and EDS observations demonstrated crystallization of the water impurities like chlorides and organics on the graphene surface under applied conditions. The changes of the graphene wettability caused by condensed contamination may cause the observed resistance changes.
EPJ Web of Conferences, 2012
Silicon vertex detector for superheavy elements (SHE) identification has been proposed. It will b... more Silicon vertex detector for superheavy elements (SHE) identification has been proposed. It will be constructed using very thin silicon detectors about 5 μm thickness. Results of test of 7.3 μm four inch silicon strip detector (SSD) with fission fragments and α particles emitted by 252 Cf source are presented
Asia Communications and Photonics Conference 2014, 2014
The influence of mechanical defects on the thermal properties of Joule heated graphene samples is... more The influence of mechanical defects on the thermal properties of Joule heated graphene samples is investigated. Modeling and experimental results reveal the hot spots attributed to non-uniform heating due to the mechanical defects of graphene.
Vacuum, 2009
Tungsten silicide formation in multilayer tungsten/silicon structure was investigated. The W-Si m... more Tungsten silicide formation in multilayer tungsten/silicon structure was investigated. The W-Si multilayers were deposited on thermally oxidized silicon wafers using the dual-target magnetron sputtering. Deposition of the whole stack of sublayers was carried out without breaking vacuum in order to eliminate contamination or oxidation of the interfaces between sublayers. Samples were annealed in the RTA furnace at temperatures ranging from 700 C up to 1050 C. Some of the structures were irradiated with argon ion beam before annealing. Reactions between sublayers were studied using SEM imaging of crosssectional cleavages and by X-ray diffraction analysis. Influence of the irradiation with argon ion beam on structural transformations was investigated using RBS analysis. It has been found that tungsten silicide formation depends on the deposition sequence. The reaction was more effective on interfaces between silicon layer deposited on tungsten then on interface between tungsten deposited on silicon. Ion beam mixing experiment showed that ion-target interaction promotes formation of the WSi 2 phase.
Vacuum, 2003
The basis of a new technology allowing the bonding of GaAs layers on various substrates is descri... more The basis of a new technology allowing the bonding of GaAs layers on various substrates is described. The method consists in the use of a two-step thermal profile during hydrogen implantation. In consequence, the transfer of GaAs layer on oxidized silicon substrate can be performed at temperatures as low as 2001C. The method opens the possibility of fabrication of high-frequency or light-emitting devices using a GaAs layer deposited on such substrates as glass, quartz or oxide crystals used in optoelectronics.
Surface Science, 2007
We describe self-assembly of arrays of micro-rings in a drying process of a mixture of H2O and C2... more We describe self-assembly of arrays of micro-rings in a drying process of a mixture of H2O and C2H5OH (1: 1) and trace amounts of NH4OH with suspended SiO2 nano-particles of 102.5 nm average diameter. A drop of 2mm diameter of the colloid is placed on a nearly ...
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Papers by Grzegorz Gawlik