Newsletter December 2019
Dear colleagues and friends of the HI-Jena,
Welcome to the December issue of our Institute Newsletter.
With this newsletter, we send you our warmest Wishes for the Holiday Season.
We wish you a Merry Christmas and a Happy New Year 2020 filled with Health, Happiness, and Successes!
As usual, below you find the latest news and informations about our institute.
Kind Regards,
Helmholtz Institute Jena
Characterization of laser-driven proton acceleration from water microdroplets
We investigated laser-driven proton acceleration with the JETI 40 laser system using water microdroplets as targets and compared it to two-dimensional particle-in-cell simulations with the code EPOCH [1]. Using a synchronized, frequency-shifted probe pulse allowed us to visualize the expansion of the droplet during and after the interaction. We found that the position of the droplets along the laser’s polarization axis has a large impact on the maximum kinetic energy of the protons emitted in the laser forward direction if laser pulses with high temporal contrast were used. This high contrast was achieved by frequency doubling the laser pulses.
Central irradiation of a droplet leads to lower maximum proton energy due to an inefficient generation of hot electrons, while significantly higher proton energies were achieved using grazing incidence of the pump laser on the target. In this latter irradiation geometry, hot electrons are generated which move along the droplet’s surface due to self-generated electric and magnetic fields. This surface current enhances the electric field at the droplet’s rear surface that is responsible for proton acceleration.
When a low-intensity pre-pulse 5 ps before the main laser pulse was introduced generating a pre-plasma, the maximum proton energy increases for normal laser incidence and becomes independent of the irradiation geometry. This is due to enhanced electron heating in comparison to the case without the pre-pulse.
Together with the measurement of the maximum proton energies, we observed the plasma expansion of the irradiated droplets on a picosecond timescale. The size and the shape of the expanded droplet reflect the behavior of the maximum proton energies. For the case of grazing incidence and without pre-pulse, the expanded plasma is larger than in the case of central illumination, while for the scan with an applied pre-pulse the form of the expanded droplet becomes independent of the droplet position.
We have thus shown that the combination of water microdroplets irradiated with frequency-doubled laser pulses and optically probed at off-harmonic wavelengths has great potential for the investigation of laser-plasma interactions.
Recently finished theses
High precision many-electron calculations for multiply-charged ions
M. Bilal
(2019)
https://www.db-thueringen.de/receive/dbt_mods_00040082
Nanoscale Coherent Diffractive Imaging using High-harmonic XUV Sources
G. Tadesse
(2019)
https://www.db-thueringen.de/receive/dbt_mods_00040692
Untersuchung lasergetriebener Protonenbeschleunigung bezüglich Vorplasmaerzeugung und räumlicher Protonendetektion
M. Mäusezahl
(2019)
Elektronendynamik in fokussierten Einzelzyklenpulsen
D. Hoff
(2019)
Recent publications
A scintillator‐based particle detector for CRYRING@ESR
C. Hahn, E. Menz, P. Pfäfflein, G. Weber, and T. Stöhlker
X-Ray Spec. 49, 338 (2020)
doi: 10.1002/xrs.3112
HILITE—A tool to investigate interactions of matter and light
N. Stallkamp, S. Ringleb, B. Arndt, M. Kiffer, S. Kumar, T. Morgenroth, G. G. Paulus, W. Quint, Th. Stöhlker, and M. Vogel
X-Ray Spec. 49, 188 (2020)
doi: 10.1002/xrs.3087
Charge state tailoring of relativistic heavy ion beams for the Gamma Factory project at CERN
F. M. Kröger, G. Weber, V. P. Shevelko, S. Hirlaender, M. W. Krasny, and Th. Stöhlker
X-Ray Spec. 49, 25 (2020)
doi: 10.1002/xrs.3039
High-precision X-ray spectroscopy of Fe ions in an EBIT using a micro-calorimeter detector: First results
M. Herdrich, A. Fleischmann, D. Hengstler, S. Allgeier, C. Enss, S. Trotsenko, T. Morgenroth, R. Schuch, G. Weber, and T. Stöhlker
X-Ray Spec. 49, 184 (2020)
doi: 10.1002/xrs.3086
Characterization of laser-driven proton acceleration from water microdroplets
G. Becker, M. Schwab, R. Lötzsch, S. Tietze, D. Klöpfel, M. Rehwald, H.-P. Schlenvoigt, A. Sävert, U. Schramm, M. Zepf, and M. Kaluza
Sci. Rep. 9, 17169 (2019)
doi: 10.1038/s41598-019-53587-3
Efficient Laser-Driven Proton Acceleration from a Cryogenic Solid Hydrogen Target
J. Polz, A. P. L. Robinson, A. Kalinin, G. A. Becker, R. Fraga, M. Hellwing, M. Hornung, S. Keppler, A. Kessler, D. Klöpfel, H. Liebetrau, F. Schorcht, J. Hein, M. Zepf, R. E. Grisenti, and M. C. Kaluza
Sci. Rep. 9, 16534 (2019)
doi: 10.1038/s41598-019-52919-7
Modeling terahertz emission from the target rear side during intense laser-solid interactions
A. Woldegeorgis, S. Herzer, M. Almassarani, S. Marathapalli, and A. Gopal
Phys. Rev. E 100, 053204 (2019)
doi: 10.1103/PhysRevE.100.053204
Spatiotemporal visualization of the terahertz emission during high-power laser-matter interaction
A. Gopal, A. Woldegeorgis, S. Herzer, and M. Almassarani
Phys. Rev. E 100, 053203 (2019)
doi: 10.1103/PhysRevE.100.053203
Coherence control in high-order harmonic generation with Laguerre-Gaussian beams
W. Paufler, B. Böning, and S. Fritzsche
Phys. Rev. A 100, 013422 (2019)
doi: 10.1103/PhysRevA.100.013422
High harmonic generation with Laguerre-Gaussian beams
W. Paufler, B. Böning, and S. Fritzsche
J. Opt. 21, 094001 (2019)
doi: 10.1088/2040-8986/ab31c3
Nondipole strong-field approximation for spatially structured laser fields
B. Böning, W. Paufler, and S. Fritzsche
Phys. Rev. A 99, 053404 (2019)
doi: 10.1103/PhysRevA.99.053404
Dichroism in two-color above-threshold ionization with twisted XUV beams and intense infrared laser fields
B. Baghdasaryan, B. Böning, W. Paufler, and S. Fritzsche
Phys. Rev. A 99, 023403 (2019)
doi: 10.1103/PhysRevA.99.023403
Coreless SQUID-based cryogenic current comparator for non-destructive intensity diagnostics of charged particle beams
V. Zakosarenko, M. Schmelz, T. Schönau, S. Anders, J. Kunert, V. Tympel, R. Neubert, F. Schmidl, P. Seidel, T. Stöhlker, D. Haider, M. Schwickert, T. Sieber, and R. Stolz
Supercond. Sci. Technol. 32, 014002 (2018)
doi: 10.1088/1361-6668/aaf206