We report on the generation of high-power ultrashort-pulsed optical vortex beams (VBs) with orbital angular momentum (OAM) of +1 in the infrared (IR) and +2 in the visible (VIS) spectral regions. The IR vortex beam was created from a Gaussian beam by employing a nanograting (S-waveplate) mode converter. With this approach we obtained an average power of up to 802 W at a wavelength of λ = 1030 nm in the IR-VB with a pulse energy of 802 µJ, a pulse duration of 460 fs, and a mode-conversion efficiency of 90.1%. By subsequent second harmonic generation, the IR-VB was frequency-doubled inside a lithium triborate (LiB3O5) crystal. An average power of up to 320 W at λ = 515 nm was generated, with 320 µJ of pulse energy, 382 fs of pulse duration, and an IR-VB to SH-VB conversion efficiency of 39.9%. The generated IR and VIS VBs were characterized by a Mach-Zehnder type interferometric measurement, confirming the helical wavefronts at these high average powers. These results show that it is possible to efficiently generate high-quality VBs at multi hundreds of watts and confirm the OAM scaling law in harmonic generation processes.
%0 Journal Article
%1 9968024
%A Loescher, André
%A Röcker, Christoph
%A Bienert, Florian
%A Graf, Thomas
%A Abdou Ahmed, Marwan
%D 2023
%J Journal of Lightwave Technology
%K OpticalVortex myown SecondHarmonicGeneration peer Laser UltrashortPulse from:andreloescher
%N 7
%P 2174-2178
%R 10.1109/JLT.2022.3225903
%T Frequency-Doubled High-Power Optical Vortex Beam With Sub 500 fs Pulse Duration
%V 41
%X We report on the generation of high-power ultrashort-pulsed optical vortex beams (VBs) with orbital angular momentum (OAM) of +1 in the infrared (IR) and +2 in the visible (VIS) spectral regions. The IR vortex beam was created from a Gaussian beam by employing a nanograting (S-waveplate) mode converter. With this approach we obtained an average power of up to 802 W at a wavelength of λ = 1030 nm in the IR-VB with a pulse energy of 802 µJ, a pulse duration of 460 fs, and a mode-conversion efficiency of 90.1%. By subsequent second harmonic generation, the IR-VB was frequency-doubled inside a lithium triborate (LiB3O5) crystal. An average power of up to 320 W at λ = 515 nm was generated, with 320 µJ of pulse energy, 382 fs of pulse duration, and an IR-VB to SH-VB conversion efficiency of 39.9%. The generated IR and VIS VBs were characterized by a Mach-Zehnder type interferometric measurement, confirming the helical wavefronts at these high average powers. These results show that it is possible to efficiently generate high-quality VBs at multi hundreds of watts and confirm the OAM scaling law in harmonic generation processes.
@article{9968024,
abstract = {We report on the generation of high-power ultrashort-pulsed optical vortex beams (VBs) with orbital angular momentum (OAM) of +1 in the infrared (IR) and +2 in the visible (VIS) spectral regions. The IR vortex beam was created from a Gaussian beam by employing a nanograting (S-waveplate) mode converter. With this approach we obtained an average power of up to 802 W at a wavelength of λ = 1030 nm in the IR-VB with a pulse energy of 802 µJ, a pulse duration of 460 fs, and a mode-conversion efficiency of 90.1%. By subsequent second harmonic generation, the IR-VB was frequency-doubled inside a lithium triborate (LiB3O5) crystal. An average power of up to 320 W at λ = 515 nm was generated, with 320 µJ of pulse energy, 382 fs of pulse duration, and an IR-VB to SH-VB conversion efficiency of 39.9%. The generated IR and VIS VBs were characterized by a Mach-Zehnder type interferometric measurement, confirming the helical wavefronts at these high average powers. These results show that it is possible to efficiently generate high-quality VBs at multi hundreds of watts and confirm the OAM scaling law in harmonic generation processes.},
added-at = {2023-03-27T08:36:24.000+0200},
author = {Loescher, André and Röcker, Christoph and Bienert, Florian and Graf, Thomas and Abdou Ahmed, Marwan},
biburl = {https://puma.ub.uni-stuttgart.de/bibtex/2232eca7b4795362b06420ac6bff5a764/ifsw},
doi = {10.1109/JLT.2022.3225903},
interhash = {a33469682cb6dae66062d14b1be4844b},
intrahash = {232eca7b4795362b06420ac6bff5a764},
issn = {1558-2213},
journal = {Journal of Lightwave Technology},
keywords = {OpticalVortex myown SecondHarmonicGeneration peer Laser UltrashortPulse from:andreloescher},
month = {April},
number = 7,
pages = {2174-2178},
timestamp = {2023-03-27T08:36:24.000+0200},
title = {Frequency-Doubled High-Power Optical Vortex Beam With Sub 500 fs Pulse Duration},
volume = 41,
year = 2023
}