Dokument-ID Dokumenttyp Autoren/innen Persönliche Herausgeber/innen Haupttitel Abstract Auflage Verlagsort Verlag Herausgeber (Institution) Erscheinungsjahr Titel des übergeordneten Werkes Jahrgang/Band ISBN Veranstaltung Veranstaltungsort Beginndatum der Veranstaltung Enddatum der Veranstaltung Ausgabe/Heft Erste Seite Letzte Seite URN DOI Lizenz Datum der Freischaltung OPUS4-38633 Zeitschriftenartikel Bonse, Jörn; Höhm, S.; Kirner, Sabrina V.; Rosenfeld, A.; Krüger, Jörg Laser-induced periodic surface structures — a scientific evergreen Laser-induced periodic surface structures (LIPSS, ripples) are a universal phenomenon and can be generated on almost any material upon irradiation with linearly polarized radiation. With the availability of ultrashort laser pulses, LIPSS have gained an increasing attraction during the past decade, since these structures can be generated in a simple single-step process, which allows a surface nanostructuring for tailoring optical, mechanical, and chemical surface properties. In this study, the current state in the field of LIPSS is reviewed. Their formation mechanisms are analyzed in ultrafast time-resolved scattering, diffraction, and polarization constrained double-pulse experiments. These experiments allow us to address the question whether the LIPSS are seeded via ultrafast energy deposition mechanisms acting during the absorption of optical radiation or via self-organization after the irradiation process. Relevant control parameters of LIPSS are identified, and technological applications featuring surface functionalization in the fields of optics, fluidics, medicine, and tribology are discussed. IEEE 2017 IEEE Journal of Selected Topics in Quantum Electronics 23 3 9000615 10.1109/JSTQE.2016.2614183 2016-12-09 OPUS4-39082 Zeitschriftenartikel Höhm, S.; Rosenfeld, A.; Krüger, Jörg; Bonse, Jörn Laser-induced periodic surface structures on zinc oxide crystals upon two-colour femtosecond double-pulse irradiation In order to study the temporally distributed energy deposition in the formation of laser-induced periodic surface structures (LIPSS) on single-crystalline zinc oxide (ZnO), two-colour double-fs-pulse experiments were performed. Parallel or cross-polarised double-pulse sequences at 400 and 800 nm wavelength were generated by a Mach-Zehnder interferometer, exhibiting inter-pulse delays up to a few picoseconds between the sub-ablation 50-fs-pulses. Twenty two-colour double-pulse sequences were collinearly focused by a spherical mirror to the sample surface. The resulting LIPSS periods and areas were analysed by scanning electron microscopy. The delay-dependence of these LIPSS characteristics shows a dissimilar behaviour when compared to the semiconductor silicon, the dielectric fused silica, or the metal titanium. A wavelength-dependent plasmonic mechanism is proposed to explain the delay-dependence of the LIPSS on ZnO when considering multi-photon excitation processes. Our results support the involvement of nonlinear processes for temporally overlapping pulses. These experiments extend previous two-colour studies on the indirect semiconductor silicon towards the direct wide band-gap semiconductor ZnO and further manifest the relevance of the ultrafast energy deposition for LIPSS formation. Bristol, UK IOP The Royal Swedish Academy of Sciences 2017 Physica Scripta 92 3 Article 034003, 1 7 10.1088/1402-4896/aa5578 2017-02-06 OPUS4-43160 Zeitschriftenartikel Heitz, J.; Plamadeala, C.; Muck, M.; Habidzadeh, H.; Baumgartner, W.; Weth, A.; Steinwender, C.; Blessberger, H.; Kellermair, J.; Kirner, Sabrina V.; Krüger, Jörg; Bonse, Jörn; Guntner, A. S.; Hassel, A. W. Laser-induced microstructures on Ti substrates for reduced cell adhesion The abstract summarizes the poster presented at the "Kardiologie im Zentrum - Fortbildung der Klinik für Kardiologie und Intensivmedizin Kepler Universitätsklinikum Linz", held between October 20th and 31st in Linz, Austria. The poster has been awarded the 2nd place of the "Best Poster Award". Gablitz, Austria Krause & Pachernegg GmbH 2017 Journal für Kardiologie - Austrian Journal of Cardiology 24 Kardiologie im Zentrum - Fortbildung der Klinik für Kardiologie und Intensivmedizin Kepler Universitätsklinikum Linz Linz, Austria 20.10.2017 31.10.2017 11-12 292 292 2017-11-28 OPUS4-43594 Buchkapitel Rosenfeld, A.; Höhm, S.; Krüger, Jörg; Bonse, Jörn Reedijk, J. Dynamics of ultrashort double-pulse laser ablation of solid surfaces Given their unique properties, ultrashort laser pulses with durations in the femtosecond to picosecond range currently open new avenues in the field of laser materials processing, resulting in groundbreaking new applications based on laser-induced surface functionalization. This article reviews the usability of temporally distributed energy deposition via double-pulse irradiation in applications based on laser ablation. This includes simple new techniques for surface nanostructuring and improved sensitivities in spectroscopic material analyses. Elsevier 2017 Reference Module in Chemistry, Molecular Sciences and Chemical Engineering, Encyclopedia of Interfacial Chemistry: Surface Science and Electrochemistry 978-0-12-409547-2 1 10 10.1016/B978-0-12-409547-2.14127-7 2018-01-03 OPUS4-42988 Beitrag zu einem Tagungsband Andree, Stefan; Heidmann, B.; Ringleb, F.; Eylers, K.; Bonse, Jörn; Boeck, T.; Schmid, M.; Krüger, Jörg Femtosecond laser pulses for photovoltaic bottom-up strategies A promising technology in photovoltaics is based on micro-concentrator solar cells, where the photovoltaic active area is realized as an array of sub-millimeter sized cells onto which the incident light is focused via microlenses. This approach allows to increase the cell efficiency and to realize much more compact modules compared to macroscopic concentrator devices. At the same time, expensive raw materials can be saved, which is of interest, for example, with respect to indium in the case of copper-indium-gallium-diselenide (CIGSe) thin film solar cells. Two methods to produce micro-sized precursors of CIGSe absorbers on molybdenum are presented using 30-fs laser pulses at 790 nm wavelength. On the one hand, a multi pulse surface structuring of the molybdenum film or the underlying glass substrate and a subsequent physical vapor deposition were used for a site-selective aggregation of indium droplets. On the other hand, a single pulse laser-induced forward transfer was utilized to selectively deposit combined copper-indium precursor pixels on the molybdenum back contact of the solar cell. Post-processing (selenization, isolation, contacting) of the laser-generated micro-sized precursors results in functional CIGSe solar cells. Mittweida Hochschule Mittweida Hochschule Mittweida 2017 Tagungsband zur 10. Mittweidaer Lasertagung 2 10. Mittweidaer Lasertagung Mittweida, Germany 16.11.2017 17.11.2017 1 4 2017-11-20 OPUS4-40421 Vortrag Bonse, Jörn Mimicking lizard-like surface structures and their fluid transport upon ultrashort laser pulse irradiation of steel The wetting behavior of material surfaces can be controlled by surface structures. We functionalized case-hardened alloyed carbon steel to modify the wetting behavior using ultrashort laser pulses (fs- to ps-range). The laser processing was performed by scanning the laser beam across the surface of initially polished flat sample material. An experimental study of the laser processing parameters (peak fluence, scan velocity, line overlap) rendered an assignment of different regimes associated with characteristic surface morphologies (laser-induced periodic surface structures, grooves, micro cones, etc.) possible. Analyzing the surface using optical as well as scanning electron microscopy allowed the identification of morphologies providing the optimum similarity to the natural skin of non-moisture havesting lizards. For mimicking skin structures of moisture-harvesting lizards, additionally a two-step laser processing strategy was established for realizing hierarchical microstructures. In this approach, micrometer-scaled capillaries (step 1) were superimposed by a laser-generated regular array of small dimples (step 2). Optical focus variation imaging measurements finally revealed the three dimensional topography of the laser processed surfaces derived from lizard skin structures. The functionality of these surfaces was analyzed in view of wetting and directional fluid transport properties. The results suggest possible applications of the laser-structured surfaces. 2017 European Materials Research Society (EMRS) Spring Meeting 2017, Symposium K “Bioinspired and biointegrated materials as new frontiers nanomaterials VII” Strasbourg, France 22.05.2017 26.05.2017 2017-05-31 OPUS4-39304 Zeitschriftenartikel Seuthe, T.; Mermillod-Blondin, A.; Grehn, M.; Bonse, Jörn; Wondraczek, L.; Eberstein, M. Structural relaxation phenomena in silicate glasses modifed by irradiation with femtosecond laser pulses Structural relaxation phenomena in binary and multicomponent lithium silicate glasses were studied upon irradiation with femtosecond (fs) laser pulses (800 nm central wavelength, 130 fs pulse duration) and subsequent thermal annealing experiments. Depending on the annealing temperature, micro-Raman spectroscopy analyses evidenced different relaxation behaviours, associated to bridging and non-bridging oxygen structures present in the glass network. The results indicate that the mobility of lithium ions is an important factor during the glass modification with fs-laser pulses. Quantitative phase contrast imaging (spatial light interference microscopy) revealed that these fs-laser induced structural modifications are closely related to local changes in the refractive index of the material. The results establish a promising strategy for tailoring fs-laser sensitivity of glasses through structural mobility. London, UK Nature Publishing Group 2017 Scientific Reports 7 43815, 1 43815, 10 urn:nbn:de:kobv:b43-393045 10.1038/srep43815 http://creativecommons.org/licenses/by/3.0/de/deed.de 2017-03-08 OPUS4-39305 Beitrag zu einem Tagungsband Bonse, Jörn; Kirner, Sabrina V.; Höhm, S.; Epperlein, Nadja; Spaltmann, Dirk; Rosenfeld, A.; Krüger, Jörg Applications of laser-induced periodic surface structures (LIPSS) Laser-induced periodic surface structures (LIPSS, ripples) are a universal phenomenon that can be observed on almost any material after the irradiation by linearly polarized laser beams, particularly when using ultrashort laser pulses with durations in the picosecond to femtosecond range. During the past few years significantly increasing research activities have been reported in the field of LIPSS, since their generation in a single-step process provides a simple way of nanostructuring and surface functionalization towards the control of optical, mechanical or chemical properties. In this contribution current applications of LIPSS are reviewed, including the colorization of technical surfaces, the control of surface wetting, the tailoring of surface colonization by bacterial biofilms, and the improvement of the tribological performance of nanostructured metal surfaces. Bellingham, USA SPIE Society of Photo-Optical Instrumentation Engineers, SPIE 2017 Proceedings of SPIE 10092 978-1-5106-0625-8 SPIE Photonics West Conference, Laser-based Micro- and Nanoprocessing XI San Francisco, USA 27.01.2017 Article UNSP 100920N, 100920N-1 100920N-9 10.1117/12.2250919 2017-03-08 OPUS4-40507 Zeitschriftenartikel Bonse, Jörn; Kirner, Sabrina; Koter, Robert; Pentzien, Simone; Spaltmann, Dirk; Krüger, Jörg Femtosecond laser-induced periodic surface structures on titanium nitride coatings for tribological applications Titanium nitride (TiN) was coated on different substrate materials, namely pure titanium (Ti), titanium alloy (Ti6Al4V) and steel (100Cr6), generating 2.5 μm thick TiN layers. Using femtosecond laser pulses (30 fs, 790 nm, 1 kHz pulse repetition rate), large surface areas (5 mm × 5 mm) of laser-induced periodic surface structures (LIPSS) with sub-wavelength periods ranging between 470 nm and 600 nm were generated and characterized by optical microscopy (OM), white light interference microscopy (WLIM) and scanning electron microscopy (SEM). In tribological tests, coefficients of friction (COF) of the nanostructured surfaces were determined under reciprocating sliding conditions (1 Hz, 1.0 N normal load) against a 10-mm diameter ball of hardened 100Cr6 steel during 1000 cycles using two different lubricants, namely paraffin oil and engine oil. It turned out that the substrate material, the laser fluence and the lubricant are crucial for the tribological performance. However, friction and wear could not be significantly reduced by LIPSS on TiN layers in comparison to unstructured TiN surfaces. Finally, the resulting wear tracks on the nanostructured surfaces were investigated with respect to their morphology (OM, SEM), depth (WLIM) and chemical composition by energy dispersive X-ray spectroscopy (EDX) and, on one hand, compared with each other, on the other hand, with non-structured TiN surfaces. Amsterdam Elsevier B.V. 2017 Applied Surface Science 418 Part B 572 579 10.1016/j.apsusc.2016.10.132 2017-06-12 OPUS4-40509 Zeitschriftenartikel Hermens, U.; Kirner, Sabrina; Emonts, C.; Comanns, P.; Skoulas, E.; Mimidis, A.; Mescheder, H.; Winands, K.; Krüger, Jörg; Stratakis, E.; Bonse, Jörn Mimicking lizard-like surface structures upon ultrashort laser pulse irradiation of inorganic materials Inorganic materials, such as steel, were functionalized by ultrashort laser pulse irradiation (fs- to ps-range) to modify the surface's wetting behavior. The laser processing was performed by scanning the laser beam across the surface of initially polished flat sample material. A systematic experimental study of the laser processing parameters (peak fluence, scan velocity, line overlap) allowed the identification of different regimes associated with characteristic surface morphologies (laser-induced periodic surface structures, grooves, spikes, etc.). Analyses of the surface using optical as well as scanning electron microscopy revealed morphologies providing the optimum similarity to the natural skin of lizards. For mimicking skin structures of moisture-harvesting lizards towards an optimization of the surface wetting behavior, additionally a two-step laser processing strategy was established for realizing hierarchical microstructures. In this approach, micrometer-scaled capillaries (step 1) were superimposed by a laser-generated regular array of small dimples (step 2). Optical focus variation imaging measurements finally disclosed the three dimensional topography of the laser processed surfaces derived from lizard skin structures. The functionality of these surfaces was analyzed in view of wetting properties. Amsterdam Elsevier, North-Holland 2017 Applied Surface Science 418 Part B 499 507 10.1016/j.apsusc.2016.12.112 2017-06-12