TY - JOUR A1 - Bonse, Jörn A1 - Seuthe, T. A1 - Grehn, M. A1 - Eberstein, M. A1 - Rosenfeld, A. A1 - Mermillod-Blondin, A. T1 - Time-resolved microscopy of fs-laser-induced heat flows in glasses N2 - Time-resolved phase-contrast microscopy is employed to visualize spatio-temporal thermal transients induced by tight focusing of a single Ti:sapphire fs-laser pulse into a solid dielectric sample. This method relies on the coupling of the refractive index change and the sample temperature through the thermo-optic coefficient dn/dT. The thermal transients are studied on a timescale ranging from 10 ns up to 0.1 ms after laser excitation. Beyond providing direct insights into the laser–matter interaction, analyzing the results obtained also enables quantifying the local thermal diffusivity of the sample on a micrometer scale. Studies conducted in different solid dielectrics, namely amorphous fused silica (a-SiO2), a commercial borosilicate glass (BO33, Schott), and a custom alkaline earth silicate glass (NaSi66), illustrate the applicability of this approach to the investigation of various glassy materials. KW - Femtosecond laser KW - Phase-contrast microscopy KW - Heat diffusion KW - Glasses PY - 2018 U6 - https://doi.org/10.1007/s00339-017-1465-5 SN - 0947-8396 SN - 1432-0630 VL - 124 IS - 1 SP - 60, 1 EP - 6 PB - Springer-Verlag AN - OPUS4-43739 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Grehn, M. A1 - Reinhardt, F. A1 - Bonse, Jörn A1 - Eberstein, M. A1 - Seuthe, T. T1 - Response to "comment on 'femtosecond laser-induced modification of potassium-magnesium silicate glasses: an analysis of structural changes by near edge x-ray absorption spectroscopy'" KW - Bond lengths KW - Glass KW - High-speed optical techniques KW - Magnesium compounds KW - Monochromators KW - Potassium compounds KW - Silicon compounds KW - XANES PY - 2013 U6 - https://doi.org/10.1063/1.4804148 SN - 0003-6951 SN - 1077-3118 VL - 102 SP - 196102-1 - 196102-2 PB - American Institute of Physics CY - Melville, NY AN - OPUS4-28520 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Grehn, M. A1 - Seuthe, T. A1 - Höfner, M. A1 - Griga, N. A1 - Theiss, C. A1 - Mermillod-Blondin, A. A1 - Eberstein, Markus A1 - Eichler, H. A1 - Bonse, Jörn T1 - Femtosecond-laser induced ablation of silicate glasses and the intrinsic dissociation energy N2 - The relation between ablation threshold fluence upon femtosecond laser pulse irradiation and the average dissociation energy density of silicate based multicomponent glass is studied. A simple model based on multiphoton absorption quantifies the absorbed energy density at the ablation threshold fluence. This energy density is compared to a calculated energy density which is necessary to decompose the glass compound into its atomic constituents. The results confirm that this energy density is a crucial intrinsic material parameter for the description of the femtosecond laser ablation threshold fluence of dielectrics. PY - 2014 U6 - https://doi.org/10.1364/OME.4.000689 SN - 2159-3930 VL - 4 IS - 4 SP - 689 EP - 700 PB - OSA CY - Washington, DC AN - OPUS4-30475 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Grehn, M. A1 - Seuthe, T. A1 - Reinhardt, F. A1 - Höfner, M. A1 - Griga, N. A1 - Eberstein, M. A1 - Bonse, Jörn T1 - Debris of potassium-magnesium silicate glass generated by femtosecond laser-induced ablation in air: An analysis by near edge X-ray absorption spectroscopy, micro Raman and energy dispersive X-ray spectroscopy N2 - The redeposited material (debris) resulting from ablation of a potassium–magnesium silicate glass upon scanning femtosecond laser pulse irradiation (130 fs, 800 nm) in air environment is investigated by means of three complementary surface analytical methods. Changes in the electronic band structure of the glass constituent Magnesium (Mg) were identified by X-ray Absorption Near Edge Structure spectroscopy (XANES) using synchrotron radiation. An up-shift of ≈0.8 eV of a specific Magnesium Κ-edge absorption peak in the spectrum of the redeposited material along with a significant change in its leading edge position was detected. In contrast, the surface left after laser ablation exhibits a downshift of the peak position by ≈0.9 eV. Both observations may be related to a change of the Mg coordinative state of the laser modified/redeposited glass material. The presence of carbon in the debris is revealed by micro Raman spectroscopy (µ-RS) and was confirmed by energy dispersive X-ray spectroscopy (EDX). These observations are attributed to structural changes and chemical reactions taking place during the ablation process. KW - Femtosecond laser ablation KW - Potassium-magnesium silicate glass KW - Debris KW - XANES KW - EDX KW - Raman spectroscopy PY - 2014 U6 - https://doi.org/10.1016/j.apsusc.2013.10.028 SN - 0169-4332 SN - 1873-5584 VL - 302 SP - 286 EP - 290 PB - Elsevier B.V. CY - Amsterdam AN - OPUS4-30454 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Grehn, M. A1 - Seuthe, T. A1 - Tsai, W.-J. A1 - Höfner, M. A1 - Achtstein, A. W. A1 - Mermillod-Blondin, A. A1 - Eberstein, M. A1 - Eichler, H.J. A1 - Bonse, Jörn T1 - Nonlinear absorption and refraction of binary and ternary alkaline and alkaline earth silicate glasses N2 - Nonlinear optical properties such as the nonlinear refractive index and nonlinear absorption are characterized by z-scan measurements for a series of silicate glasses upon irradiation with laser pulses of 130 fs duration and 800 nm center wavelength. The stoichiometry of the silicate glasses is varied systematically to reveal the influence of the glass composition on the nonlinear optical properties. Additionally, the thermal properties such as glass–transformation temperature and thermal expansion coefficient are obtained from dilatometric measurements. It is found that the nonlinear refractive index is mainly related to the silica matrix. The nonlinear absorption is increased with the addition of network–forming ions. PY - 2013 U6 - https://doi.org/10.1364/OME.3.002132 SN - 2159-3930 VL - 3 IS - 12 SP - 2132 EP - 2140 PB - OSA CY - Washington, DC AN - OPUS4-29649 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Grehn, M. A1 - Tsai, W.J. A1 - Höfner, M. A1 - Seuthe, T. A1 - Bonse, Jörn A1 - Mermillod-Blondin, A. A1 - Rosenfeld, A. A1 - Hennig, J. A1 - Achtstein, A. W. A1 - Theiss, C. A1 - Woggon, U. A1 - Eberstein, M. A1 - Eichler, H.J. T1 - Nonlinear optical properties of binary and ternary silicate glasses upon near-infrared femtosecond pulse laser irradiation N2 - Some nonlinear optical properties such as the nonlinear refractive index and the nonlinear effective absorption, as well as the laser-induced single-pulse ablation threshold are characterized for a series of binary and ternary silicate glasses upon irradiation with near-infrared femtosecond laser pulses (800 nm, 130 fs). The laser-induced ablation threshold varies from 2.3 J/cm² in case of potassium silicate glass up to 4.3 J/cm² in case of Fused Silica. Nonlinear refractive indices are qualitatively similar within the range 1.7-2.7×10-16 cm²/W. Complementary optical and physico-chemical properties like band gap energy and the glass transformation temperature have been measured for all the glasses. T2 - International symposium on high power laser ablation 2012 CY - Santa Fe, NM, USA DA - 30.04.2012 KW - Laser-induced damage threshold KW - Laser ablation KW - Nonlinear refractive index KW - Silicate glass systems KW - Glass transformation temperature KW - Coefficient of thermal expansion PY - 2012 SN - 978-0-7354-1068-8 U6 - https://doi.org/10.1063/1.4739918 N1 - Serientitel: AIP conference proceedings – Series title: AIP conference proceedings VL - 1464 SP - 660 EP - 670 AN - OPUS4-26318 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mermillod-Blondin, A. A1 - Seuthe, T. A1 - Eberstein, M. A1 - Grehn, M. A1 - Bonse, Jörn A1 - Rosenfeld, A. ED - Gorecki, C. ED - Asundi, A. K. ED - Osten, W. T1 - Quantitative estimate of fs-laser induced refractive index changes in the bulk of various transparent materials N2 - Over the past years, many applications based on laser-induced refractive index changes in the volume of transparent materials have been demonstrated. Ultrashort pulse lasers offer the possibility to process bulky transparent materials in three dimensions, suggesting that direct laser writing will play a decisive role in the development of integrated micro-optics. At the present time, applications such as 3D long term data storage or embedded laser marking are already into the phase of industrial development. However, a quantitative estimate of the laser-induced refractive index change is still very challenging to obtain. On another hand, several microscopy techniques have been recently developed to characterize bulk refractive index changes in-situ. They have been mostly applied to biological purposes. Among those, spatial light interference microscopy (SLIM), offers a very good robustness with minimal post acquisition data processing. In this paper, we report on using SLIM to measure fs-laser induced refractive index changes in different common glassy materials, such as fused silica and borofloat glass (B33). The advantages of SLIM over classical phase-contrast microscopy are discussed. T2 - Optical Micro- and Nanometrology V CY - Brussels, Belgium DA - 14.04.2014 KW - Laser material processing KW - Quantitative phase-contrast microscopy KW - Spatial light interference microscopy KW - Nanometrology PY - 2014 U6 - https://doi.org/10.1117/12.2051590 VL - 9132 SP - Artikel 91320X, 1 EP - 6 AN - OPUS4-30638 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seuthe, T. A1 - Grehn, M. A1 - Mermillod-Blondin, A. A1 - Bonse, Jörn A1 - Eberstein, M. T1 - Compositional dependent response of silica-based glasses after femtosecond laser pulse irradiation N2 - Femtosecond laser pulse irradiation of inorganic glasses allows a selective modification of the optical properties with very high precision. This results in the possibility for the production of three-dimensional functional optical elements in the interior of glass materials, such as optical data storage, waveguide writing, etc. The influence of the chemical glass composition to the response upon ultrashort laser irradiation has not been studied systematically. For that, simple silicabased model glasses composed of systematically varying alkaline- and earth-alkaline components were prepared, irradiated on the surface and in the volume with single fs-laser pulses (~130 fs, 800 nm), and were subsequently analyzed by means of micro-Raman spectroscopy and quantitative phase contrast microscopy in order to account for changes in the glass structure and for alterations of the optical refractive index, respectively. The Raman spectroscopic studies of the laser-irradiated spots revealed no change in the average binding configuration (the so called Q-structure), but local changes of bond-angles and bond-lengths within the glass structure structure. Those changes are explained by structural relaxation of the glass network due to densification caused by a transient laser-induced plasma generation and the following shock wave and other thermal phenomena. Glasses with a low amount of network modifiers show changes in the Si-O network while glasses with a high amount of network modifiers react primarily via variation of the nonbridging oxygen ions. The results are discussed in terms of possible structural response mechanisms and conclusions are outlined regarding glass compositions with technical suitability for fs-laser modifications. T2 - Laser-induced damage in optical materials CY - Boulder, Colorado, USA DA - 2013-09-22 KW - Femtosecond laser modifications KW - Raman spectroscopy KW - Glass KW - Femtosecond phenomena KW - Networks KW - Silica KW - Laser irradiation KW - Lasers KW - Micro raman spectroscopy KW - Microscopy KW - Optical components KW - Optical storage PY - 2013 U6 - https://doi.org/10.1117/12.2028713 N1 - Serientitel: SPIE proceedings series – Series title: SPIE proceedings series VL - 8885 SP - 1 EP - 8(?) AN - OPUS4-29539 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seuthe, T. A1 - Grehn, M. A1 - Mermillod-Blondin, A. A1 - Bonse, Jörn A1 - Eberstein, M. T1 - Requirements on glasses for femtosecond-laser based micro-structuring N2 - In this work, glasses with systematically varied compositions were manufactured and irradiated by single Ti:sapphire fs-laserpulses (800 nm, 120 fs), focused at the surface and into the bulk of the glass materials. The samples were tested for their ablation threshold fluence as well as for structural changes using µ-Raman-spectroscopy. Correlations between the glass composition, the material-ablation on the glass surface and the permanent changes of the refractive index inside the glass volume after the irradiation by fs-laser pulses were obtained. The results show, that the structural modifications found at the surface of the glasses and inside its volume are closely related. However, while the ablation threshold fluence of the glass surface primarily depends on the glass dissociation energy, the permanent refractive index change inside the volume is rather determined by its ability for absorbing the fs-laser pulses and the subsequent relaxation processes. The results of this work provide some guidance on how the glass composition can be varied in order to optimize the fs-laser induced modification of dielectrics. T2 - 11th International Conference on Ceramic Interconnect & Ceramic Microsystems Technologies CY - Dresden, Germany DA - 20.04.2015 PY - 2015 SN - 978-1-5108-0456-2 U6 - https://doi.org/10.4071/CICMT-TA24 SP - 47 EP - 53 PB - Curran CY - Red Hook, NY, USA AN - OPUS4-34755 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Seuthe, T. A1 - Grehn, M. A1 - Mermillod-Blondin, A. A1 - Eichler, H.J. A1 - Bonse, Jörn A1 - Eberstein, M. T1 - Structural modifications of binary lithium silicate glasses upon femtosecond laser pulse irradiation probed by micro-Raman spectroscopy N2 - The effects of single femtosecond laser pulse irradiation (130 fs pulse duration, 800 nm center wavelength) on the structure of binary lithium silicate glasses of varying chemical compositions were investigated by micro-Raman spectroscopy. Permanent modifications were generated at the surface of the glass samples with varying laser fluences in the ablative regime and evaluated for changes in the corresponding Raman band positions and bandwidths. For increasing laser fluences, the position of certain Raman bands changed, indicating an increase in the mass density of the glass inside the irradiated area. Simultaneously, the widths of all investigated bands increased, indicating a higher degree of disorder in the glass structure with respect to bond-angle and bond-length variations. PY - 2013 U6 - https://doi.org/10.1364/OME.3.000755 SN - 2159-3930 VL - 3 IS - 6 SP - 755 EP - 764 PB - OSA CY - Washington, DC AN - OPUS4-28372 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Seuthe, T. A1 - Höfner, M. A1 - Reinhardt, F. A1 - Tsai, W.J. A1 - Bonse, Jörn A1 - Eberstein, M. A1 - Eichler, H.J. A1 - Grehn, M. T1 - Femtosecond laser-induced modification of potassium-magnesium silicate glasses: An analysis of structural changes by near edge x-ray absorption spectroscopy N2 - The effects of femtosecond laser pulse irradiation on the glass structure of alkaline silicate glasses were investigated by x-ray absorption near edge structure spectroscopy using the beamline of the Physikalisch-Technische Bundesanstalt at the electron synchrotron BESSY II in Berlin (Germany) by analyzing the magnesium Κ-edge absorption peak for different laser fluences. The application of fluences above the material modification threshold (2.1 J/cm²) leads to a characteristic shift of ~1.0 eV in the Κ-edge revealing a reduced (~3%) mean magnesium bond length to the ligated oxygen ions (Mg-O) along with a reduced average coordination number of the Mg ions. KW - Glass KW - Glass structure KW - Laser beam effects KW - Magnesium compounds KW - Potassium compounds KW - XANES PY - 2012 U6 - https://doi.org/10.1063/1.4723718 SN - 0003-6951 SN - 1077-3118 VL - 100 IS - 22 SP - 224101-1 EP - 224101-3 PB - American Institute of Physics CY - Melville, NY AN - OPUS4-25918 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Seuthe, T. A1 - Mermillod-Blondin, A. A1 - Grehn, M. A1 - Bonse, Jörn A1 - Wondraczek, L. A1 - Eberstein, M. T1 - Structural relaxation phenomena in silicate glasses modifed by irradiation with femtosecond laser pulses N2 - 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. KW - Femtosecond laser KW - Silicate glasses KW - Raman spectroscopy KW - Structural relaxation KW - Refractive index PY - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-393045 SN - 2045-2322 VL - 7 SP - 43815, 1 EP - 43815, 10 PB - Nature Publishing Group CY - London, UK AN - OPUS4-39304 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -