Interferometric gravitational wave detection — a (quantum) metrological challenge

Since the first direct detection of gravitational waves in 2015, we have gained an entirely new observation window to the universe. The sensitivity of these interferometers is so incredible that quantum effects of the laser light have become limiting. Ultra-precisely stabilised lasers do not suffice; non-classical light is already routinely employed in the current generation gravitational wave detectors (e.g. aLIGO & AdVirgo). Other noise sources, such as seismic and thermal noise, pose further challenges for next-generation detectors.

To achieve ever-higher detection rates for meaningful gravitational wave astronomy, ever-greater detection sensitivity is required. I will introduce the principle of interferometric gravitational wave detection and highlight some of the advanced technologies implemented. I will conclude my talk by showing some further possibilities, as well as options for quantum noise reduction in laser interferometry and the broader field of quantum optics. I will also briefly introduce the German Centre for Astrophysics.