Dynamics of femtosecond laser-produced plasma ions

Ion distribution and ablation depth measurements of a fs-ps laser-irradiated solid tin target Deuzeman, M. J.; Stodolna, A. S.; Leerssen, E. E. B.; Antoncecchi, A.; Spook, N.; Kleijntjens, T.; Versluis, J.; Witte, S.; Eikema, K. S. E.; Ubachs, W. Link to publication in University of Groningen/UMCG research database Citation for published version (APA): Deuzeman, M. J., Stodolna, A. S., Leerssen, E. E. B., Antoncecchi, A., Spook, N., Kleijntjens, T., ... Versolato, O. O. (2017). Ion distribution and ablation depth measurements of a fs-ps laser-irradiated solid tin target. Journal of Applied Physics, 121(10), [103301]. https://doi.org/10.1063/1.4977854 Copyright Other than for strictly personal use, it is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license (like Creative Commons).Take-down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. Ion distribution and ablation depth measurements of a fs-ps laser-irradiated solid tin target The ablation of solid tin surfaces by a 800-nanometer-wavelength laser is studied for a pulse length range from 500 fs to 4.5 ps and a fluence range spanning from 0.9 to 22 J/cm 2 . The ablation depth and volume are obtained employing a high-numerical-aperture optical microscope, while the ion yield and energy distributions are obtained from a set of Faraday cups set up under various angles. We found a slight increase of the ion yield for an increasing pulse length, while the ablation depth is slightly decreasing. The ablation volume remained constant as a function of pulse length. The ablation depth follows a two-region logarithmic dependence on the fluence, in agreement with the available literature and theory. In the examined fluence range, the ion yield angular distribution is sharply peaked along the target normal at low fluences but rapidly broadens with increasing fluence. The total ionization fraction increases monotonically with fluence to a 5%-6% maximum, which is substantially lower than the typical ionization fractions obtained with nanosecond-pulse ablation. The angular distribution of the ions does not depend on the laser pulse length within the measurement uncertainty. These results are of particular interest for the possible utilization of fs-ps laser systems in plasma sources of extreme ultraviolet light for nanolithography. Published by AIP Publishing. [http://dx

“…12) at 2 J/cm 2 (at 500 fs pulse length) to $3%-4% (Ref. 44) at 5 J/cm 2 (50 fs). We find similar values, reaching 5 and 6% in our fluence range for 1.0 and 4.5 ps, respectively.…”

Section: B Peak Fluence Dependencementioning

confidence: 94%

Ion distribution and ablation depth measurements of a fs-ps laser-irradiated solid tin target

Deuzeman

Stodolna

Leerssen

et al. 2017

“…We notice that for ablation of copper with the Ti:Sa Gaussian output beam, we measured an average fluence value F av,G ¼ 0.45 J/cm 2 . 40,41 Thus, the following analysis refers to an average fluence of the vortex beam F % 3 Â F av,G .…”

Section: Resultsmentioning

confidence: 99%

Direct femtosecond laser ablation of copper with an optical vortex beam

Anoop

Fittipaldi

Rubano

et al. 2014

Self Cite

Laser surface structuring of copper is induced by laser ablation with a femtosecond optical vortex beam generated via spin-to-orbital conversion of the angular momentum of light by using a q-plate. The variation of the produced surface structures is studied as a function of the number of pulses, N, and laser fluence, F. After the first laser pulse (N¼1), the irradiated surface presents an annular region characterized by a corrugated morphology made by a rather complex network of nanometer-scale ridges, wrinkles, pores, and cavities. Increasing the number of pulses (21000) and a deep crater is formed. The nanostructure variation with the laser fluence, F, also evidences an interesting dependence, with a coarsening of the structure morphology as F increases. Our experimental findings demonstrate that direct femtosecond laser ablation with optical vortex beams produces interesting patterns not achievable by the more standard beams with a Gaussian intensity profile. They also suggest that appropriate tuning of the experimental conditions (F, N) can allow generating micro- and/or nano-structured surface for any specific application

“…As detailed below, the measured fluence threshold for ablation was estimated to be F th ¼ (0.43 6 0.08) J/cm 2 , in our experimental conditions. 52 The plasma plume optical emission was imaged on an ICCD camera equipped with a 1024 Â 1024 array. Twodimensional (2D) images of the NPs plume self-emission were registered.…”

Section: Experimental Methodsmentioning

confidence: 99%

Ultrashort laser ablation of bulk copper targets: Dynamics and size distribution of the generated nanoparticles

Tsakiris

Anoop

Ausanio

et al. 2014

Self Cite

We address the role of laser pulse fluence on expansion dynamics and size distribution of the nanoparticles produced by irradiating a metallic target with an ultrashort laser pulse in a vacuum, an issue for which contrasting indications are present in the literature. To this end, we have carried out a combined theoretical and experimental analysis of laser ablation of a bulk copper target with 50 fs, 800 nm pulses, in an interval of laser fluencies going from few to several times the ablation threshold. On one side, molecular dynamics simulations, with two-temperature model, describe the decomposition of the material through the analysis of the evolution of thermodynamic trajectories in the material phase diagram, and allow estimating the size distribution of the generated nanoaggregates. On the other side, atomic force microscopy of less than one layer nanoparticles deposits on witness plates, and fast imaging of the nanoparticles broadband optical emission provide the corresponding experimental characterization. Both experimental and numerical findings agree on a size distribution characterized by a significant fraction (90%) of small nanoparticles, and a residual part (10%) spanning over a rather large size interval, evidencing a weak dependence of the nanoparticles sizes on the laser pulse fluence. Numerical and experimental findings show a good degree of consistency, thus suggesting that modeling can realistically support the search for experimental methods leading to an improved control over the generation of nanoparticles by ultrashort laser ablation