Researchers from the HiLASE Advanced Laser Development department collaborated on a new study published in the Current Optics and Photonics journal. Ye Jin Oh, Jiří Mužík, Yuya Koshiba, Pawel Sikocinski, Martin Smrž, and Tomáš Mocek worked with researchers from Hanyang University (In Chul Park, Eun Kyoung Park, Ji Won Kim) and Korea Institute of Industrial Technology (Hoon Jeong).
The study reports on the results from a high-power Yb:YAG thin-disc laser with radial or azimuthal polarization incorporating an intracavity S-waveplate. The research team was able to achieve 10.8 W and 10.2 W output for radial and azimuthal polarizations, respectively, at 1030 nm with slope efficiencies of ~23%.
The results were limited due to lowered laser efficiency, but show that the use of a mode transformation-optimized S-waveplate in combination with a careful cavity design should lead to an improvement in laser efficiency, opening up the prospect of radially or azimuthally polarized Yb:YAG thin-disc laser output power on the level of tens or hundreds of watts. These results are promising for advanced applications which require precise control of beam polarisations.
ABSTRACT
A high-power Yb:YAG thin-disc laser with radial or azimuthal polarization incorporating an intracavity S-waveplate is reported. Depending on the rotational angle of the S-waveplate placed in the cavity, a Yb:YAG thin-disc laser yields 10.8 W and 10.2 W of continuous-wave outputs with radial and azimuthal polarization for an incident pump power of 131 W, corresponding to slope efficiencies of 22.9% and 23.7%, respectively. The output characteristics for each polarization state were investigated in detail by analysing the insertion loss and the mode overlap efficiency due to the S-waveplate. Further prospects for power scaling will be discussed.
