Researchers at the Institute for Gravitational Physics at Leibniz University Hannover and at the Max Planck Institute for Gravitational Physics (Albert Einstein Institute) have long been leading institutions in gravitational-wave research and are co-initiators of the Einstein Telescope. The Einstein Telescope (ET) is a planned European gravitational-wave observatory. Scientists from these institutes have now successfully secured funding as part of the Einstein Telescope preparatory program funded by the German Federal Ministry of Research, Technology, and Space.
Together with other partner institutions in Germany they will develop core technologies for the Einstein Telescope. These key technologies are essential for the observatory to achieve its planned and unprecedented measurement accuracy.
New laser and squeezed light sources
The research group led by Benno Willke and Henning Vahlbruch will develop new laser and squeezed light sources for the Einstein Telescope. The laser sources provide the ultra-stable and pure laser light. It is used to detect the minute changes in length that gravitational waves will cause in the Einstein Telescope’s 10-kilometer-long underground measurement arms. Squeezed light sources modify the quantum mechanical component of the background noise in gravitational-wave detectors. This enables them to make much more precise observations. In addition, the research group will investigate and further develop new methods for stabilizing the laser sources used in the Einstein Telescope.
For laser development, the researchers are collaborating within the well-established structures of the QuantumFrontiers Cluster of Excellence. On the Braunschweig side of the consortium, the research groups led by Stefanie Kroker (TU Braunschweig) and Uwe Sterr (Physikalisch-Technische Bundesanstalt) are part of the project. In addition, the Laser Zentrum Hannover e. V., a research group led by Peter Weßels within the Laser Development Department, is a further cluster partner in the team. Finally, the University of Jena and the Fraunhofer Institute for Laser Technology are also involved. The joint projects will receive around 3.3 million euros in funding over the next three years.
Optical simulations and new methods for noise suppression
In another collaborative effort, the research groups led by Gudrun Wanner and David Wu will lay the groundwork for detailed and in-depth investigations of the optics and the measurement methods of the planned Einstein Telescope. To this end, they will use specialized software and optical simulations. In addition they will, using the institute’s 10-meter prototype of a gravitational-wave detector, investigate new methods to suppress various low-frequency disturbances affecting the Einstein Telescope’s measurements. Both projects are closely interlinked and operate synergetically.
For these projects, which are being carried out in collaboration with the University of Erlangen-Nuremberg, Helmut Schmidt University in Hamburg, and the University of Hamburg, the researchers will receive about 1 million euros in funding over the next three years.
Hannover: A hub for gravitational-wave research
The funding secured underscores the importance of Hanover as a research hub within the QuantumFrontiers Cluster of Excellence network and the leading role of the Institute for Gravitational Physics at Leibniz University Hannover and the Max Planck Institute for Gravitational Physics (Albert Einstein Institute) in the field of gravitational-wave research. Since the very beginning of planning the Einstein Telescope, experts from these institutes have been among the leading figures in this major project and continue to hold leadership roles within the project and the Einstein Telescope Scientific Collaboration.
The Einstein Telescope
The Einstein Telescope is a flagship European scientific project. Starting in the 2030s, it will open up entirely new avenues for exploring the Universe by observing gravitational waves from merging neutron stars and black holes with unprecedented precision. Gravitational waves are tiny ripples in space and time; their first detection in 2015 opened up a whole new chapter in astronomy.
The Einstein Telescope will be about ten times more sensitive than the current state-of-the-art instruments of the second generation (LIGO, Virgo, KAGRA). A decision about the site location of the European observatory is expected in 2027.
