Unlocking LISA core technology: verification of the LISA measurement chain (MSc theses)
Job Offer from May 13, 2019
LISA (Laser Interferometer Space Antenna) is an ambitious space mission currently under development. It aims to listen to gravitational-wave sources which are only audible from space and which promise plenty of exciting new science. The mission consists of three spacecraft forming a triangle with 2.5 million km (~7 times the earth-moon distance) arm length. Laser interferometry will be used to measure the distances between test masses on board the satellite with picometer precision to ultimately detect gravitational waves which would slightly change these distances.
At the AEI, we set up an experiment to test the core pieces of LISA's measurement technology, which covers the laser-interferometric phase readout by an electronic device called Phasemeter down to the challenging picometer precision. This experiment brings together state-of-the-art technology in optics as well as in analog and digital (FPGA-based) signal processing.
In the future, we want to extend this experiment to test more aspects of the LISA measurement chain, including additional functions like e.g. data transfer, absolute ranging and clock transfer between satellites via laser modulations. This is necessary to enable a novel interferometry scheme called Time-Delay-Interferometry (TDI). Additionally, we want to verify the performance shown with low laser power levels(~100 pW) as will be present in LISA.
The extension would cover the following parts:
- consolidate the current setup
- add additional optical hardware like electro-optical modulators (EOMs) for the laser modulation
- add/implement the digital electronics in the Phasemeter required for the additional functions (data transfer etc.)
- add a well-defined and controlled attenuation for the laser power
- be the first to measure picometer performance in a LISA-TDI-like metrology setup!
A future student in this experiment will work primarily with optics, extending the optical setup, e.g. with the aforementioned EOMs etc. and/or with VHDL for digital circuit design on FPGAs as well as software development (embedded processors and external data processing) for the extension of the Phasemeter with the additional functions.
Please contact Dr. Thomas Schwarze for further information.