Gravitational waves are extremely small distortions of space-time that are generated by the acceleration of objects and then propagate as waves at the speed of light. A gravitational wave hitting the earth can be measured using detectors by creating optical interference in an interferometer with a highly stable laser. Therefore, current gravitational wave detectors use solid-state lasers at a wavelength of 1064 nm. Longer wavelengths are needed for cryogenically cooled mirrors, such as those used in next-generation detectors. The LZH scientists will therefore develop laser sources that emit at a wavelength of 2 µm. For this purpose, they will investigate fiber amplifiers' dynamic behavior and power scaling with different active doping in this wavelength range.

The LZH work is part of the collaborative project "3G-GWD: Third-Generation Gravitational-Wave Telescopes," in which several German scientific institutions are preparing for two international projects in the field of gravitational-wave research: The planned Einstein telescope in Europe and the Cosmic Explorer in the USA.

Partners in the project "3G-GWD: Third Generation Gravitational Wave Telescopes" are, in addition to the LZH, the Rheinisch-Westfälische Technische Hochschule Aachen (coordination), the Forschungsverbund Berlin e.V., the University of Hamburg, the Technische Universität Carolo-Wilhelmina zu Braunschweig, the Leibniz Universität Hannover, the FH Münster, the Karlsruhe Institute of Technology and the Friedrich-Alexander-Universität Erlangen-Nürnberg.

The project is funded by the German Federal Ministry of Education and Research (project no.: 05A23ZE1).