%0 Journal Article %1 Boubekraoui2023 %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 %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{Boubekraoui2023, 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 = {2023-12-07T13:23:30.000+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/a.boubekraoui}, day = 07, doi = {10.1007/s00340-023-08144-2}, interhash = {99d45af5e2773b8268b06afb849c847b}, intrahash = {26a42b51f4908ea9dca9ed9efa58a9eb}, issn = {1432-0649}, journal = {Applied Physics B}, keywords = {}, month = dec, number = 1, pages = 4, timestamp = {2023-12-07T12:23:30.000+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 }