We report on the design, fabrication, and implementation of a single-layer resonant waveguide-grating (RWG) mirror on a sapphire substrate. Our goal is to enhance these optics capability to withstand high intra-cavity power densities by exploiting the superior thermal properties of sapphire. The RWG was implemented as an intra-cavity folding mirror in an Yb:YAG thin-disk laser to generate linearly polarized and spectrally stabilized radiation. A linearly polarized output power of 191 W with an optical efficiency of 39\% was obtained in multi-mode operation. This corresponds to a power density of 52 kW/cm2 on the RWG, for which the increase of its surface temperature was measured to be 12 K, which resulted in a 46-fold reduction of the surface temperature rise dependence on the intra-cavity power density with respect to what has been reported for a RWG on a fused silica substrate. In near fundamental-mode operation, a linearly polarized emission with an output power of 90 W, an optical efficiency of 30\%, and a spectral bandwidth of 28 pm FWHM was obtained.
%0 Journal Article
%1 Bashir2023
%A Bashir, Danish
%A Boubekraoui, Ayoub
%A Mourkioti, Georgia
%A Li, Fangfang
%A Karvinen, Petri
%A Kuittinen, Markku
%A Mackenzie, Jacob. I.
%A Graf, Thomas
%A Abdou Ahmed, Marwan
%D 2023
%J Applied Physics B
%K laser myown peer
%N 1
%P 4
%R 10.1007/s00340-023-08144-2
%T Sapphire-based resonant waveguide-grating mirrors: advancing their intra-cavity power density capability
%U https://doi.org/10.1007/s00340-023-08144-2
%V 130
%X We report on the design, fabrication, and implementation of a single-layer resonant waveguide-grating (RWG) mirror on a sapphire substrate. Our goal is to enhance these optics capability to withstand high intra-cavity power densities by exploiting the superior thermal properties of sapphire. The RWG was implemented as an intra-cavity folding mirror in an Yb:YAG thin-disk laser to generate linearly polarized and spectrally stabilized radiation. A linearly polarized output power of 191 W with an optical efficiency of 39\% was obtained in multi-mode operation. This corresponds to a power density of 52 kW/cm2 on the RWG, for which the increase of its surface temperature was measured to be 12 K, which resulted in a 46-fold reduction of the surface temperature rise dependence on the intra-cavity power density with respect to what has been reported for a RWG on a fused silica substrate. In near fundamental-mode operation, a linearly polarized emission with an output power of 90 W, an optical efficiency of 30\%, and a spectral bandwidth of 28 pm FWHM was obtained.
@article{Bashir2023,
abstract = {We report on the design, fabrication, and implementation of a single-layer resonant waveguide-grating (RWG) mirror on a sapphire substrate. Our goal is to enhance these optics capability to withstand high intra-cavity power densities by exploiting the superior thermal properties of sapphire. The RWG was implemented as an intra-cavity folding mirror in an Yb:YAG thin-disk laser to generate linearly polarized and spectrally stabilized radiation. A linearly polarized output power of 191 W with an optical efficiency of 39{\%} was obtained in multi-mode operation. This corresponds to a power density of 52 kW/cm2 on the RWG, for which the increase of its surface temperature was measured to be 12 K, which resulted in a 46-fold reduction of the surface temperature rise dependence on the intra-cavity power density with respect to what has been reported for a RWG on a fused silica substrate. In near fundamental-mode operation, a linearly polarized emission with an output power of 90 W, an optical efficiency of 30{\%}, and a spectral bandwidth of 28 pm FWHM was obtained.},
added-at = {2024-02-08T09:42:15.000+0100},
author = {Bashir, Danish and Boubekraoui, Ayoub and Mourkioti, Georgia and Li, Fangfang and Karvinen, Petri and Kuittinen, Markku and Mackenzie, Jacob. I. and Graf, Thomas and Abdou Ahmed, Marwan},
biburl = {https://puma.ub.uni-stuttgart.de/bibtex/226a42b51f4908ea9dca9ed9efa58a9eb/thomas_graf},
day = 07,
doi = {10.1007/s00340-023-08144-2},
interhash = {99d45af5e2773b8268b06afb849c847b},
intrahash = {26a42b51f4908ea9dca9ed9efa58a9eb},
issn = {1432-0649},
journal = {Applied Physics B},
keywords = {laser myown peer},
month = dec,
number = 1,
pages = 4,
timestamp = {2024-02-08T09:42:15.000+0100},
title = {Sapphire-based resonant waveguide-grating mirrors: advancing their intra-cavity power density capability},
url = {https://doi.org/10.1007/s00340-023-08144-2},
volume = 130,
year = 2023
}