TY - CONF A1 - Bonse, Jörn T1 - Chemical and topographical changes upon sub-100-nm LIPSS formation on titanium alloy N2 - Laser-induced periodic surface structures (LIPSS) have gained remarkable attention as they represent a universal phenomenon that is often accompanying laser-processing. Such LIPSS enable a large variety of different surface functionalizations for applications in the fields of optics, fluidics, tribology, or medicine. Moreover, so-called “high spatial frequency LIPSS” (HSFL) provide an appealing and straightforward way for surface nanostructuring featuring spatial periods even below 100 nm – far beyond the optical diffraction limit. However, the imposed surface functionalities are usually caused by both, topographic and chemical surface alterations. For exploring these effects in detail, multi-method characterizations were performed here for HSFL on processed Ti- 6Al- 4V alloy upon irradiation with near-infrared ps-laser pulses (1030 nm wavelength, ~1 ps pulse duration, 1 – 400 kHz pulse repetition rate) under different laser and scan processing conditions. The sample characterization involved morphological and topographical investigations by scanning electron microscopy (SEM), atomic force microscopy (AFM), stylus profilometry (SP), and white light interference microscopy (WLIM), as well as near-surface chemical analyses by X-ray photoelectron spectroscopy (XPS), hard X-ray photoelectron spectroscopy (HAXPES) and depth-profiling time-of-flight secondary ion mass spectrometry (TOF-SIMS). The results allow to qualify the laser ablation depth, the geometrical HSFL characteristics and provide detailed insights into the depth extent and the nature of the ps-laser-induced near-surface oxidation. Significance for medical applications will be outlined. T2 - E-MRS Spring Meeting 2023 CY - Strasbourg, France DA - 29.05.2023 KW - Laser-induced periodic surface structures (LIPSS) KW - Ultrashort laser processing KW - Hard X-ray photoelectron spectroscopy (HAXPES) KW - Time-offlight secondary ion mass spectrometry (ToF-SIMS) KW - Ti6Al4V alloy PY - 2023 AN - OPUS4-58531 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - BOOK A1 - Stoian, R. A1 - Bonse, Jörn T1 - Ultrafast Laser Nanostructuring — The Pursuit of Extreme Scales N2 - Long seen as “a solution seeking a problem,” laser pulses are nowadays – more than 60 years after their first practical demonstration – paramount in shaping and structuring matter. Harnessing their capabilities to direct intense beams of light, the number of scientific and technological developments and daily-life applications is continuously increasing. Today, the presence of lasers is ubiquitous in all sites of scientific and technological interest, from the most advanced research laboratories to industrial factories and medical hospitals. The directionality of the laser beam determines equally a local character on lightmatter interaction and as such a local modification to a material target. Furthermore, the coherence of laser radiation enables near-field or far-field scattering and interference effects that widen significantly the capabilities of controlling and tracking laser-matter interactions in space and time. Already with the advent of lasers, powerful beams of light have been directed at solid materials for a variety of purposes, making this application as old as the laser itself. The roots of the major applications for laser structuring were developed already in the 1960s, setting the base of both theoretical and experimental studies on laser ablation, with the number of publications expanding explosively during the next decades. Within this dynamic context, laser processing of materials experienced an impressive development over the years. Laser processing means specifically the capability to structure and tailor a material on its surface or even within its volume, rendering new functions and properties that are impacting the mechanical, electrical, or optical characteristics of the material. These properties are scaledependent, generating thus over the years an equally impressive quest for spatial or temporal resolution. Therefore, the developments in laser engineering with major breakthroughs, notably in pulse duration and power, always closely accompanied the efforts in material structuring with two milestones in sight: (1) yield and (2) resolution. Every step in shrinking the laser pulse duration led to a subsequent strong-impact development in process precision – particularly when the ultrashort pulse durations surpassed the fundamental electron-phonon relaxation times. Thus, minimizing heat diffusion, the advent of pulses with duration smaller than molecular or lattice vibration times has managed to confine the spatial resolution to the optical diffraction limit and sometimes even beyond. The nanoscale was already in sight at the turn of the millennium. An important question may be raised now; is there any fundamental limit in the processing resolution, a barrier defined by the intrinsic properties of light and matter? The answer has an inherently multidisciplinary nature, following the conversion of free-propagating electromagnetic radiation into material-confined energy potentially usable to drive or transform matter, and will be the focus of the present book. Relying on the experience and expertise of the leading researchers in the field, the present book intends to explore the current efforts in achieving laser processing resolution beyond the diffraction limit, laying down a perspective towards extreme laser nanostructuring. Following the most recent advances and developments, it puts forward a concept of extreme processing scales enabled by optical pulses that are able to bypass diffraction limits and achieve structuring characteristic scales beyond 100 nm. This objective can be achieved by a comprehensive understanding on how light can change matter and how, in turn, matter can change light, allowing jointly for actively controlling light and material processes. In order to give an extended perspective on the current state-of-the-art in the field of precision laser structuring, the book is divided into three main parts. The first part of the book (Part I: Fundamental Processes) offers a perspective into the fundamentals of laser-matter interaction on extreme spatial scales, with a description of the most advanced modeling efforts in understanding energy deposition in matter, a plethora of material-relaxation pathways, as well as advanced concepts for probing and observing matter in motion. Roadmaps for energy localization will be developed, and the atomistic perspective of laser ablation visualized. Theoretical modelling enables in-depth insights on ultrafast quantum processes at the nanoscale. Laser-driven self-organization at surfaces will be dissected regarding the question of how light drives material periodic patterns down to the nanoscale, explored and transmitted to its ultimate limits of an atomic printer, and immediately complemented by the unprecedented capabilities of ultrafast in-situ observation approaches for tracking the laser-induced material response with extreme spatial and temporal resolution. In the second part of the book (Part II: Concepts of Extreme Nanostructuring), distinct concepts will be developed and explored that allow confinement of light and harnessing of a material response restricted to nano- or mesoscopic scales at surfaces or in the volume of irradiated materials. A special focus will be on optical near-field related approaches for localizing light on scales even below the optical diffraction limit and plasmonic printing. Spatial and temporal beam-shaping and tailored interference techniques are discussed in the context of ultrashort laser pulses, and insights into some extreme states of matter realized by the tight confinement of laser energy are presented. The ultimate limits of writing waveguides in the bulk of dielectrics and for manifesting 3D-nanolithography are elucidated. Plasma-based surface treatments can significantly enhance the vertical precision of surface processing through etching processes. Finally, the third part of the book (Part III: Applications) leads us to a number of resuming applications, unveiling the tremendous capabilities of surface functionalization through laser micro- and nanostructuring, assessing the 3D-writing of waveguides in the bulk of dielectrics or semiconductors for enabling new branches of integrated photonics, and summarizing related applications ranging from nanophotonics to nanofluidics and from optical sensing to biomedical applications, including the latest capabilities of refractive eye surgery. This part will analyze the applications’ compatibility in yield and reproducibility with current industrial requirements, costs, and intellectual property aspects. It expands the involved spatial scales by more than eight orders of magnitude, when extending extremely small structures featuring sizes of few tens of nanometers to larger dimensions in the meter range. Thus, from surfaces to the bulk, from subtractive to additive manufacturing approaches, from advanced theoretical frames to practical technological processes – we invite the readers here to an exciting journey into the varicolored landscape of extreme laser nanostructuring. The idea of this book project was seeded in early 2020. We were delighted about the numerous and extremely positive responses from the laser-processing community, quickly receiving commitments for more than 30 individual book chapters. About 2500 communications later, the book is published. We would like to thank all authors of this book project for their insightful and detailed chapters, reviewing and reporting on this fascinating topic of the pursuit of extreme scales in ultrafast laser nanostructuring. Moreover, we would like to acknowledge the professional help and guidance of the staff of Springer Nature. Finally, we hope you will enjoy reading this book as much as we have enjoyed putting it together. Saint Etienne, France Razvan Stoian Berlin, Germany Jörn Bonse December 2022 KW - Laser nanostructuring KW - Surface engineering KW - Nonlinear lithography KW - Self-organization KW - Laser-induced periodic surface structures, LIPSS PY - 2023 SN - 978-3-031-14752-4 SN - 978-3-031-14751-7 DO - https://doi.org/10.1007/978-3-031-14752-4 SN - 0342-4111 VL - 239 SP - 1 EP - 1245 PB - Springer Nature Switzerland AG CY - Cham ET - 1 AN - OPUS4-57294 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bonse, Jörn T1 - Chemical analyses of ps-laser generated LIPSS and Spikes on titanium alloy by HAXPES, XPS, and depth-profiling TOF-SIMS N2 - Laser-induced periodic surface structures (LIPSS) and their combination with self-ordered microstructures forming hierarchical Spikes enable a large variety of different surface functionalizations for applications in the fields of optics, fluidics, tribology, or medicine. Moreover, high spatial frequency LIPSS (HSFL) provide an appealing and straightforward way for surface nanostructuring featuring spatial periods even below 100 nm – far beyond the optical diffraction limit. However, the imposed surface functionalities are usually caused by both, topographic and chemical surface alterations. For exploring these effects in detail, multi-method characterizations were performed here for HSFL and hierarchical Spikes processed on Ti-6Al-4V alloy upon irradiation with near-infrared ps-laser pulses (1030 nm wavelength, ~1 ps pulse duration, 1 – 400 kHz pulse repetition rate) under different laser and scan processing conditions. The following sample characterization involved morphological and topographical investigations by scanning electron microscopy (SEM), atomic force microscopy (AFM), stylus profilometry (SP), and white light interference microscopy (WLIM), as well as near-surface chemical analyses by X-ray photoelectron spectroscopy (XPS), hard X-ray photoelectron spectroscopy (HAXPES) and depth-profiling time-of-flight secondary ion mass spectrometry (TOF-SIMS). The results allow to qualify the laser ablation depth, the geometrical HSFL/Spikes characteristics and provide detailed insights into the depth extent and the nature of the ps-laser-induced near-surface oxidation arising from the laser-processing in ambient air and into the relevance of heat-accumulation effects at high pulse repetition rates. Moreover, the direct comparison of the HAXPES and XPS data reveals the role of surface-covering organic contaminants adsorbed from the ambient atmosphere without the uncertainties and potential sputter reduction potentially caused by ion-sputter depth profiling. T2 - 11th International LIPSS Workshop CY - Madrid, Spain DA - 27.09.2023 KW - Laser-induced periodic surface structures (LIPSS) KW - Ultrafast laser processing KW - Hard X-ray photoelectron spectroscopy (HAXPES) KW - Time-of-flight secondary ion mass spectrometry (ToF-SIMS) KW - Ti6Al4V alloy PY - 2023 AN - OPUS4-58532 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bonse, Jörn T1 - Erzeugung und Charakterisierung anisotroper Nanostrukturen durch Ultrakurzpulslaser N2 - Der Vortrag gibt einen Überblick über die Erzeugung und Charakterisierung anisotroper Nanostrukturen mittels ultrakurzgepulster Laserstrahlung. Besonderes Augenmerk liegt dabei auf dem Phänomen der sogenannten Laser-induzierten periodischen Oberflächen-Nanostrukturen auf dielektrischen Werkstoffen und ihrer zeitlichen Dynamik. Weitere Beispiele von Volumen-Nanostrukturen aus der Literatur werden diskutiert. T2 - 21. Treffen des DGG-DKG Arbeitskreises „Glasig-kristalline Multifunktionswerkstoffe“ CY - Mainz, Germany DA - 22.02.2024 KW - Laser-induzierte periodische Oberflächen-Nanostrukturen KW - Quarzglas KW - Saphir KW - Bessel-Strahlen PY - 2024 AN - OPUS4-59565 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bonse, Jörn T1 - Advances in ultrafast laser manufacturing: nanostructures, thin films, and scaling perspectives N2 - Advanced ultrafast laser technology is a rapidly growing field that currently enables many new industrial and scientific applications. During the last decades, this has been significantly driven by the availability of high-repetition-rate laser sources and novel beam delivery concepts. At the laser side, Moore’s law equally manifests for ultrafast laser technologies, since the average output power of such lasers doubles approximately every two years. This development is mainly driven by the increase of the pulse repetition rates of energetic laser pulses, currently enforcing the development of smart beam control and novel scanning strategies for preventing heat-accumulation and plasma-shielding effects during laser-based materials processing. This keynote presentation addresses the advantages, recent developments, and perspectives of laser processing with ultrashort laser pulses. A special focus is laid on the tailored structuring of thin films as well as the manufacturing and probing of sub-diffraction surface nanostructures – an ongoing race to extreme scales. Current limitations are identified and an outlook to future scaling perspectives will be provided. T2 - SPIE Photonics Europe 2024 Conference, Symposium "Lasers and Photonics for Advanced Manufacturing" CY - Strasbourg, France DA - 07.04.2024 KW - Ultrafast laser processing KW - Laser-induced periodic surface structures (LIPSS) KW - Surface functionalization KW - Laser technology KW - Time-resolved analysis PY - 2024 UR - https://spie.org/photonics-europe/presentation/Advances-in-ultrafast-laser-manufacturing--nanostructures-thin-films-and/13005-36#_=_ AN - OPUS4-59852 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bonse, Jörn T1 - Funktionalisierung durch laser-induzierte periodische Oberflächenstrukturen N2 - Der Vortrag gibt einen Überblick über die vielfältigen Möglichkeiten der Oberflächenfunktionalisierung mittels Mikro- und Nanostrukturierung durch Ultrakurzpuls-Lasermaterialbeabeitung. Dies schließt eine Diskussion des Phänomens der Laser-induzierten periodischen Oberflächenstrukturen (LIPSS, engl.: Laser-induced Periodic Surface Structures, Ripples), sowie deren Klassifikation und Bildungsmechanismen mit ein. Ein Schwerpunkt der Präsentation liegt auf der Diskussion verschiedener Anwendungsmöglichkeiten der LIPSS in Bereichen der Optik, Fluidik, Tribologie und Medizin, sowie auf einem Ausblick auf die industrielle Skalierbarkeit der LIPSS-Technologie. T2 - 1. Netzwerktreffen 2024 des UKPL-Innovationsnetzwerks CY - Rostock, Germany DA - 11.03.2024 KW - Laser-induced Periodic Surface Structures (LIPSS) KW - Oberflächenfunktionalisierung KW - Mikrostrukturen KW - Nanostrukturen KW - Ultrakurzpuls-Laserbearbeitung PY - 2024 AN - OPUS4-59657 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bonse, Jörn A1 - Schwibbert, Karin T1 - Laserstrukturierte Oberflächen: Ein Weg zur Kontrolle der Biofilmbildung? N2 - Bakterielle Biofilme stellen in medizinischen und industriellen Bereichen ein ernsthaftes Problem dar. Eine der größten gesellschaftlichen Herausforderungen liegt in der zunehmenden Resistenz von Bakterien gegen Biozide, die bei antimikrobiellen Behandlungen eingesetzt werden, z.B. durch übermäßigen Einsatz in Medizin, Industrie und Landwirtschaft oder durch Reinigung und Desinfektion in Privathaushalten. Daher sind neue effiziente bakterienabweisende Strategien, die den Einsatz von Bioziden vermeiden, dringend erforderlich. Ein vielversprechender Weg zur Erzielung bakterienabweisender Oberflächen liegt in der berührungslosen und aseptischen großflächigen Laserbearbeitung von technischen Oberflächen. Maßgeschneiderte Oberflächentexturen, ermöglicht durch verschiedene Laserbearbeitungsstrategien, die zu topographischen Skalen im Bereich von Nanometern bis Mikrometern führen, können eine Lösung für diese Herausforderung darstellen. In dem Vortrag wird ein Überblick über den aktuellen Stand der Technik bei der subtraktiven Texturierung von Laseroberflächen zur Kontrolle der Biofilmbildung bei verschiedenen Bakterienstämmen und in unterschiedlichen Umgebungen gegeben. Auf der Grundlage spezifischer Eigenschaften von Bakterien und laserbearbeiteten Oberflächen werden die Herausforderungen antimikrobieller Oberflächendesigns erörtert und zukünftige Richtungen aufgezeigt. T2 - GRAVOSeminar, GRAVOmer Kompetenznetzwerk CY - Online meeting DA - 28.02.2024 KW - Laser-Materialbearbeitung KW - Ultrakurzpuls-Laser KW - Biofilme KW - Antibakterielle Oberflächen KW - Oberflächenfunktionalisierung PY - 2024 UR - https://gravomer.de/veranstaltungen-anzeigen/laserstrukturierte-oberflaechen-ein-weg-zur-kontrolle-der-biofilmbildung AN - OPUS4-59594 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Kaczmarek, D. A1 - Albert, T. J. A1 - Munz, Martin A1 - Sturm, Heinz A1 - Bonse, Jörn T1 - Erratum: “Structure formation on the surface of indium phosphide irradiated by femtosecond laser pulses” [J. Appl. Phys. 97, 013538 (2005)] N2 - This erratum publishes some corrections to the article “Structure formation on the surface of indium phosphide irradiated by femtosecond laser pulses” [J. Appl. Phys. 97, 013538 (2005)]. PY - 2024 DO - https://doi.org/10.1063/5.0222903 SN - 0021-8979 SN - 1089-7550 VL - 136 IS - 4 SP - 1 EP - 2 PB - American Institute of Physics CY - Melville, NY AN - OPUS4-60690 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bonse, Jörn T1 - Chemical and topographical analyses of ps-laser generated HSFL on titanium alloy N2 - Laser-induced periodic surface structures (LIPSS) enable a large variety of different surface functionalizations for applications in the fields of optics, fluidics, tribology, or medicine. Moreover, high spatial frequency LIPSS (HSFL) provide an appealing and straightforward way for the generation of surface nanostructures featuring spatial periods even below 100 nm – far beyond the optical diffraction limit. However, the imposed surface functionalities are usually caused by both, topographic and chemical surface alterations. For exploring these effects in detail, multi-method characterization was performed here for HSFL processed on Ti-6Al-4V alloy upon irradiation with near-infrared ps-laser pulses (1030 nm wavelength, ~1 ps pulse duration, 1 – 400 kHz pulse repetition rate) under different scan processing conditions. The subsequent sample characterization involved morphological and topographical investigations by scanning electron microscopy (SEM), atomic force microscopy (AFM), stylus profilometry (SP), as well as near-surface chemical analyses by X-ray photoelectron spectroscopy (XPS), hard X-ray photoelectron spectroscopy (HAXPES) and depth-profiling time-of-flight secondary ion mass spectrometry (TOF-SIMS). The results allow to qualify the laser ablation depth, the geometrical HSFL characteristics and provide detailed insights into the depth extent and the nature of the ps-laser-induced near-surface oxidation arising from the laser-processing in ambient air and into the relevance of heat-accumulation effects at high pulse repetition rates. Moreover, the direct comparison of the HAXPES and XPS data reveals the role of surface-covering organic contaminants adsorbed from the ambient atmosphere without ion-sputter depth profiling. Furthermore, reduction of the oxides by sputtering can be avoided. T2 - SPIE Photonics Europe 2024 Conference, Symposium "Lasers and Photonics for Advanced Manufacturing" CY - Strasbourg, France DA - 07.04.2024 KW - Laser-induced periodic surface structures (LIPSS) KW - Ultrafast laser processing KW - Nanostructures KW - Chemical analyses PY - 2024 UR - https://spie.org/photonics-europe/presentation/Chemical-and-topographical-analyses-of-ps-laser-generated-high-spatial/13005-69#_=_ AN - OPUS4-59853 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kaczmarek, D. A1 - Bonse, Jörn T1 - Capabilities and limitations of Sipe’s first principles LIPSS theory: current aspects and directions N2 - This presentation elucidates the fundamentals and capabilities of John E. Sipe’s first principles theory (1983) of laser-induced periodic surface structures (LIPSS), representing an analytical mathematical approach (Green’s formalism) to calculate the absorption of electromagnetic radiation at a microscopically rough surface via the so-called efficacy factor. It includes a discussion of assumptions made in the theory and resulting limitations, such as the restriction to a near-surface layer (the so-called “selvedge”), the lack of any material response, or missing inter-pulse feedback phenomena being relevant in typical multi-pulse irradiation conditions. The influence of the angle of incidence, the polarization direction (s-pol. or p-pol.), the optical properties (dielectric permittivity) of the irradiated materials, as well as its surface roughness and its specific encoding in the theory via a shape factor (s) and a filling factor (f) are addressed. A simplifying mathematical reformulation (without changing the validity range) of Sipe’s theory in the form of 14 complex-valued equations published in 2005 is motivated, as well as the necessity of some minor adjustments for non-normal incident radiation - revealed in a very recent Erratum. Starting with 2009, extensions of the original theory were developed, e.g., the analytical Sipe-Drude model in order to include intra-pulse transient changes of the optical properties of the material. Finite-difference time-domain (FDTD) numerical simulations successfully confirmed in 2012 the validity of the Sipe-Drude approach. Moreover, the FDTD formalism can be extended to sub-surface regions and can be combined with a material response (topography) modelling for iteratively considering inter-pulse feedback phenomena. Finally, we will provide characteristic examples of Sipe’s efficacy factor for typical material classes (metals, semiconductors, dielectrics), we will explain how the results can be interpreted, and line out how the Sipe theory may be extended further. T2 - 12th International LIPSS Workshop CY - Leipzig, Germany DA - 11.09.2024 KW - Laser-induced periodic surface structures (LIPSS) KW - Theory KW - Green's formalism KW - Scattering waves KW - Finite-difference time-domain calculations PY - 2024 AN - OPUS4-61098 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Böttcher, Katrin A1 - Kraft, Sebastian A1 - Weise, Matthias A1 - Bonse, Jörn A1 - Krüger, Jörg T1 - Publisher correction: X-ray emission during ultrafast laser grooving N2 - This is a corrigendum to the original article "X-ray emission during ultrafast laser grooving" that was published in the journal "Applied Physics A", vol. 131 (2025), article 651 (doi 10.1007/s00339-025-08728-z). PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-648868 DO - https://doi.org/10.1007/s00339-025-08882-4 SN - 0947-8396 VL - 131 IS - 11 SP - 1 PB - Springer CY - Berlin AN - OPUS4-64886 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bonse, Jörn T1 - Bacterial adhesion on ultrashort pulse laser processed surfaces ― more than size matters! N2 - Bacterial biofilms are aggregates of bacterial cells, often attached to a surface and enclosed by a self-produced extracellular matrix which confers increased stress tolerance and resistance to cleaning. Biofilm formation leads to biofouling which gives rise to high costs in numerous technical settings due to biocorrosion and biodegradation. However, biofilms can also be attractive for industrial settings such as wastewater treatment systems or for soil bioremediation processes. Hence, the control of bacterial adhesion to a surface is of major concern. Surface topography strongly influences bacterial adhesion. Therefore, one promising way to achieve bacteria-guiding surfaces lies in the contactless and aseptic large-area laser processing of technical surfaces. We used short and ultrashort pulsed laser systems to generate different surface textures, mainly high-spatial-frequency and low-spatial-frequency laser-induced periodic surface structures, LIPSS (HFSL and LFSL), on Ti, Ti-alloy, steel, and polymers (PET and PE). Pristine (polished) and laser processed samples were subjected to bacterial adhesion experiments with two different Escherichia coli strains and Staphylococcus aureus as test organisms. The bacterial strains differed in their cell wall structure (grampositive vs. gramnegative strains), in size, shape, the occurrence of cell appendages, and in their biofilm forming capabilities. Adhesion patterns were analyzed microscopically and compared regarding the respective test strain and surface topography. Our results revealed that adhesion behavior strongly depends not only on the material’s topography and chemistry, but also on the specific bacterial strain, the presence of cell appendages, and ambient growth conditions. T2 - 13th International Conference on Photoexcited Processes and Applications, ICPEPA-13 CY - Lecce, Italy DA - 14.09.2025 KW - Biofilm KW - Bacterial adhesion KW - Laser-induced periodic surface structures (LIPSS) KW - Ultrashort laser pulses PY - 2025 AN - OPUS4-64166 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bonse, Jörn T1 - Laser Nanotexturierung von Metalloberflächen zur Reduktion von Reibung und Verschleiß N2 - Die Reduktion von Reibung und Verschleiß in technischen Systemen bietet ein großes Potenzial zur Reduktion von CO2-Emissionen. Dieser Beitrag diskutiert die Erzeugung und tribologische Charakterisierung von Ultrakurzpuls-generierten Nanostrukturen auf Metallen (Stahl, Titan). Besonderes Augenmerk wird dabei auf die Rolle der laserinduzierten Oxidschicht im Zusammenspiel mit verschleißreduzierenden Additiven in ölbasierten Schmiermitteln gerichtet. T2 - Online Abendvortrag beim AWT Härterei- und Werkstoffkreis Bodensee der Arbeitsgemeinschaft Wärmebehandlung + Werkstofftechnik e.V. CY - Online meeting DA - 16.01.2025 KW - Additive KW - Laser-induzierte periodische Nanostrukturen KW - Reibungsreduktion KW - Verschleißreduktion PY - 2025 AN - OPUS4-62432 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bonse, Jörn T1 - Laser Nanotexturierung von Metalloberflächen zur Reduktion von Reibung und Verschleiß N2 - Die Reduktion von Reibung und Verschleiß in technischen Systemen bietet ein großes Potenzial zur Reduktion von CO2-Emissionen. Dieser Beitrag diskutiert die Erzeugung und tribologische Charakterisierung von Ultrakurzpuls-generierten Nanostrukturen auf Metallen (Stahl, Titan). Besonderes Augenmerk wird dabei auf die Rolle der laserinduzierten Oxidschicht im Zusammenspiel mit verschleißreduzierenden Additiven in ölbasierten Schmiermitteln gerichtet. T2 - Internationale Bodensee Fachtagung „Wärmebehandlung und Oberflächentechnik zur Verbesserung von Tribologie und Verschleissbeständigkeit" CY - Feldkirch, Austria DA - 20.03.2025 KW - Additive KW - Laser-induzierte periodische Nanostrukturen KW - Reibungsreduktion KW - Verschleißreduktion PY - 2025 AN - OPUS4-62757 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bonse, Jörn T1 - Generation and characterization of anisotropic nanostructures using ultrashort pulsed lasers N2 - The lecture gives an overview of the generation and characterization of anisotropic nanostructures using ultrashort pulsed laser radiation. Special attention will be paid to the phenomenon of so-called laser-induced periodic surface structures (LIPSS) on various materials. One focus will be on dielectrics and the dynamics of nanostructure formation. Further examples of bulk nanostructures from the literature will be discussed. T2 - 8th UKP-Workshop: Ultrafast Laser Technology CY - Aachen, Germany DA - 08.04.2025 KW - Laser-induced Periodic Surface Structures (LIPSS) KW - Dielectrics KW - Surface Nanostructures KW - Volume Nanostructures PY - 2025 AN - OPUS4-62947 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bonse, Jörn T1 - Ultrafast optical probing of laser-induced formation of periodic surface nanostructures N2 - Laser-induced Periodic Surface Structures (LIPSS, ripples) are a universal phenomenon and can be generated in a contactless, single-step process on almost any type of solid upon irradiation with intense laser pulses. They represent a (quasi-)periodic modulation of the surface topography in the form of a linear grating and are typically formed in a “self-ordered” way in the focus of a coherent laser beam. Thus, they are often accompanying laser material processing applications. The structural sizes of LIPSS typically range from several micrometers down to less than 100 nanometers – far beyond the optical diffraction limit – while their orientations exhibit a clear correlation with the local polarization direction of the laser radiation. From a theoretical point of view, a controversial debate has emerged during the last decades, whether LIPSS originate from electromagnetic effects (seeded already during the laser irradiation) – or whether they emerge from matter-reorganization processes (distinctly after the laser irradiation). From a practical point of view, however, LIPSS represent a simple and robust way for the nanostructuring of solids that allows creating a wide range of different surface functionalities featuring applications in optics, tribology, medicine, energy technologies, etc. The presentation provides an overview of current theories on LIPSS and the quest to achieve ever smaller surface nanostructures. The historical development of the fundamental ideas behind LIPSS is presented, together with experimental approaches that make it possible to distinguish between the various LIPSS formation scenarios. Time-resolved experimental methods are required to investigate the dynamics of their formation. The presentation focuses on ultrafast time-resolved optical (pump-probe) techniques that can be used for localized point measurements or microscopic imaging, utilizing the reflection, diffraction, or coherent scattering of the probe radiation at the emerging LIPSS, while simultaneously capturing information about rapid melting, ablation, and solidification phenomena. However, given the sub-micrometric spatial periods of LIPSS, their analysis using optical radiation employed in far-field techniques remained a challenge. Therefore, short wavelengths of the probe beam in the UV range or even below are required to overcome the diffraction limit imposed in the optical spectral range. Fourth-generation light sources, namely short-wavelength (XUV or X-ray) short-pulse free-electron lasers (FELs), offer new and fascinating possibilities for resolving laser-induced structure formation on surfaces in the sub-micrometer to nanometer range and in time domains from picoseconds to several nanoseconds with a resolution in the sub-picosecond regime. On laser-irradiated semiconductor surfaces, this unique spatio-temporal resolution enables the detection of early signs of coherent/plasmonic electromagnetic scattering effects, followed by the excitation of hydrodynamic capillary waves – providing new insights into the above-mentioned debate. Recent experiments at the European XFEL used fs-time-resolved small-angle X-ray scattering (fs-SAXS) and even fs-time-resolved grazing incidence small-angle X-ray scattering (fs-GISAXS), combined with grazing-incidence diffraction (fs-GID), to reveal the dynamics of the formation of nanometric LIPSS on metals. T2 - CINSaT Herbstkolloquium 2025 CY - Kassel, Germany DA - 05.11.2025 KW - Laser-induced periodic surface structures (LIPSS) KW - Ultrashort laser pulses KW - Pump-probe measurements KW - Free-electron laser KW - Small angle X-ray scattering (SAXS) PY - 2025 AN - OPUS4-64633 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bonse, Jörn T1 - Bacterial adhesion on ultrashort pulse laser processed surfaces ― more than size matters! N2 - Bacterial biofilms are aggregates of bacterial cells, often attached to a surface, and enclosed by a self-produced extracellular matrix which confers increased stress tolerance and resistance to cleaning. Biofilm formation leads to biofouling which gives rise to high costs in numerous technical settings due to biocorrosion and biodegradation. However, biofilms can also be attractive for industrial settings such as wastewater treatment systems or for soil bioremediation processes. Hence, the control of bacterial adhesion to a surface is of major concern. Surface topography strongly influences bacterial adhesion. Therefore, one promising way to achieve bacteria-guiding surfaces lies in the contactless and aseptic large-area laser processing of technical surfaces. We used short and ultrashort pulsed laser systems to generate different surface textures, mainly high-spatial-frequency and low-spatial-frequency laser-induced periodic surface structures, LIPSS (HFSL and LFSL), on Ti, Ti-alloy, steel, and polymers (PET and PE). Pristine (polished) and laser processed samples were subjected to bacterial adhesion experiments with two different Escherichia coli strains and Staphylococcus aureus as test organisms. The bacterial strains differed in their cell wall structure (grampositive vs. gramnegative strains), in size, shape, the occurrence of cell appendages, and in their biofilm forming capabilities. Adhesion patterns were analyzed microscopically and compared regarding the respective test strain and surface topography. Our results revealed that adhesion behavior strongly depends not only on the material’s topography and chemistry, but also on the specific bacterial strain, the presence of cell appendages, and ambient growth conditions. T2 - 13th International LIPSS Workshop CY - Enschede, Netherlands DA - 29.10.2025 KW - Bacterial adhesion KW - Biofilm KW - Laser-induced periodic surface structures (LIPSS) KW - Ultrashort laser pulses PY - 2025 AN - OPUS4-64632 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hülagü, Deniz A1 - Hirahara, Kenta A1 - Fischer, Daniel A1 - Florian, Camilo A1 - Schusterbauer, Robert A1 - Ermilova, Elena A1 - Krüger, Jörg A1 - Unterreiner, Andreas-Neil A1 - Bonse, Jörn A1 - Hertwig, Andreas T1 - Using imaging ellipsometry to understand femtosecond laser materials processing of group IV materials N2 - Laser materials processing is an important tool for creating and shaping new materials. Laser machining, especially with ultrashort pulses offers the modification of surfaces, thin coatings, and bulk materials with an unprecedented precision and control. The most desired feature of pulsed laser processing in the femtosecond range is that the heat-affected zone in the irradiated material will be extremely small. To better understand the mechanisms involved during laser irradiation, it is important to analyse the outcome of light-matter interaction with spectroscopic methods. Ellipsometry, especially spectroscopic imaging ellipsometry (SIE), has become an important tool for this in recent times, as it gives access to local layer thicknesses, materials dielectric functions, and features like changes in surface roughness. This work includes an overview over our recent studies examining near-infrared fs-laser surface processing of different group IV materials. The superficial phase change of silicon from crystalline to amorphous has been investigated in the past as the result of laser processing strongly depends on the crystal orientation. Moreover, SIE is capable of determining the properties of buried a-Si interfaces with micrometer lateral and sub-nanoneter vertical precision. Additionally, the growth of native and laser-induced oxides can be revealed. T2 - ICSE10 - 10th International Conference on Spectroscopic Ellipsometry CY - Boulder, CO, USA DA - 08.06.2025 KW - Laser surface ablation KW - Amorphous Carbon KW - Silicon KW - Correlative Imaging Ellipsometry PY - 2025 AN - OPUS4-63633 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Frechilla, A. A1 - Martínez, E. A1 - del Moral, J. A1 - López-Santos, C. A1 - Frechilla, J. A1 - Nuñez-Gálvez, F. A1 - López-Flores, V. A1 - de la Fuente, G.F. A1 - Hülagü, Deniz A1 - Bonse, Jörn A1 - González-Elipe, A.R. A1 - Borrás, A. A1 - Angurel, L.A. T1 - Influence of near-edge Laser-Induced Periodic Surface Structures (LIPSS) on the electrical properties of fs-laser-machined ITO microcircuits N2 - Scalable, cost-effective methods for processing transparent electrodes at the microscale are pivotal to advancing in electrochemistry, optoelectronics, microfluidics, and energy harvesting. In these fields, the precise fabrication of micrometric circuits and patterns plays a critical role in determining device performance, material compatibility, and integration with added-value substrates. In this context, Laser Subtractive Manufacturing stands out as a suitable microfabrication technique for its adaptability to diverse materials and complex configurations, as well as its straightforward scalability, affordability, and eco-friendly nature. However, a challenge in micromachining metals and metal oxides is the inherent formation of Laser-Induced Periodic Surface Structures (LIPSS), which can significantly impair electrical conductivity, particularly when circuit dimensions fall within the micrometer range. Herein, we investigate the micromachining of electrical microcircuits using ultrashort pulse laser systems applied to transparent indium tin oxide (ITO) thin films. We analyze the formation of LIPSS at the edges of the micromachined regions associated with the Gaussian distribution of the energy within the laser spot, and the impact of these structures on the electrical properties of the circuits. Thus, we systematically evaluate the influence of LIPSS orientation and periodicity by fabricating various circuit patterns using femtosecond lasers at green (515 nm) and ultraviolet (UV) (343 nm) wavelengths. A correlation between electrical resistivity measurements and microstructure analysis, as determined by field emission scanning electron and transmission electron microscopy, reveals distinct effects of the formed nanostructures depending on the laser source and its polarization. For the green wavelength, the edge side regions where LIPSS are oriented perpendicular to the ITO track exhibit a resistance higher by a factor just above two compared to those where LIPSS are parallel. Additionally, UV laser processing results in a pronounced reduction of ITO thickness at the boundary between the LIPSS region and the substrate. The mechanisms for the formation of LIPSS with both wavelengths are also discussed. Furthermore, we have determined that in narrow conductive tracks with a width ranging from 6 to 8 µm, the impact of LIPSS is particularly significant because the LIPSS structured region occupies a dominant fraction of the total width. KW - ITO KW - Laser-induced periodic surface structures (LIPSS) KW - Laser subtractive manufacturing KW - fs-laser processing KW - Electrical properties PY - 2026 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-655921 DO - https://doi.org/10.1016/j.apsusc.2026.166415 SN - 0169-4332 VL - 731 SP - 1 EP - 13 PB - Elsevier B.V. AN - OPUS4-65592 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -