COLLOQUIUM "Laser interferometers with a twist - noisy lasers for low-frequency gravitational wave detection" by Oliver Gerberding (U Hamburg)

Friday 22 Nov 2024, 11:00 → 12:00 Europe/Amsterdam

Ground-based gravitational wave detectors have initialised a new era of astronomy by observing mergers of black holes and neutron stars. Future, third generation detectors like the Einstein Telescope will further revolutionise our gravitational wave observation capabilities by increasing the sensitivity not only broadband, but especially through improvements at frequencies below 10 Hz. Reducing the noise at these frequencies requires the development of new instrumental technologies that can overcome the various limitations in this regime.
In this talk I will give an overview of laser interferometric gravitational wave detectors, their sources and limitations, and I will specifically talk about two new laser interferometric techniques that we study to reduce critical low-frequency noise sources in future detectors. These techniques, Deep Frequency Modulation Interferometry and Tunable Coherence Interferometry, are both relying on modulating lasers, introducing intentional disturbances, or artificial noise, that then provide new means of extracting information or suppressing parasitic optical signals. I will motive the study of each technique, provide a short introduction to them, and then discuss the state of their laboratory testing and development.