Ulrich Johann

TL;DR: The first results of the LISA Pathfinder in-flight experiment demonstrate that two free-falling reference test masses, such as those needed for a space-based gravitational wave observatory like LISA, can be put in free fall with a relative acceleration noise with a square root of the power spectral density.

TL;DR: The Macroscopic Quantum Resonators (MAQROI) project as mentioned in this paper proposes a mission to probe the quantum transition for increasingly massive objects, testing the predictions of quantum theory for objects in a size and mass regime unachievable in ground-based experiments.

TL;DR: In this paper, the authors present a compact heterodyne interferometer utilizing polarizing optics combined with the method of differential wavefront sensing (DWS) serving as a demonstrator for a complete optical readout system of the proof mass translation and attitude aboard the LISA satellites.

TL;DR: In this paper, a heterodyne Mach-Zehnder interferometer was selected as the baseline for the SMART-2 mission and its design and expected performance were described.

TL;DR: The LISA Technology Package (LTP) is a technology demonstration mission in preparation for the LISA space-borne gravitational wave detector as discussed by the authors, which is a central part of the LTP is the optical metrology package (heterodyne interferometer with phasemeter) that measures the distance between two test masses with a noise level of 10 pm Hz−1/2 between 3 mHz and 30 mHz.