Exploring the frontiers of science
Morgane Zeoli is a PhD student at the University of Liège (ULiège). She focuses on cryogenic sensors that are useful in reducing the noise sources that disturb the Einstein Telescope detectors, such as the thermal noise of the mirror coatings and suspensions. To address these challenges, the mirrors of the Einstein Telescope will be suspended on super-insulators and subjected to cryogenic temperatures (below -130°C).
Zeoli’s dissertation is about developing efficient cold instrumentation. In a recent study, she placed several key elements of an interferometer in a cryostat (a mechanical cooler) to test the performance of these optical elements at cryogenic temperatures or, if that didn’t work, to find a solution. At cryogenic temperatures, the properties of some materials, such as semiconductors, change in unexpected ways. This fascinating research for the Einstein Telescope may also have implications in other technological fields.
What inspires you?
“As a young researcher, my fascination with space and technological challenges has always driven me to explore the boundaries of science. Gravitational wave detectors perfectly fit this challenge. Detecting these waves from Earth requires instruments that go beyond current capabilities, creating a playground for technological innovation. These technical challenges motivate me and give me the feeling of contributing to something big.”
How did you get involved with the Einstein Telescope project?
“My research journey really took shape during my final project at the Precision Mechatronics Laboratory of ULiège, led by Professor Christophe Collette. Working on the suspension of an inertia sensor fascinated me. This experience was the springboard to a PhD offer on cryogenic inertia sensors. This field, which I discovered almost by chance, seemed a logical and enriching next step.”
And after the PhD, what happens next?
“If the Einstein Telescope is built in the Euregio Meuse-Rhine, I see myself continuing in this field after the PhD, maybe as a postdoc. Participating in a project of this scale is an incredible opportunity, and I would love to follow its evolution until the end. The future of gravitational wave detectors is promising, with new types of detectors in development. Each new instrument offers a different way to explore the universe. Contributing to this progress gives me immense satisfaction.”
What are the biggest technical challenges?
“My work involves developing cryogenic inertia sensors capable of measuring extremely small displacements at temperatures of just 20K (-253°C). The challenges are numerous: materials shrink and lose elasticity, electronics perform poorly, and the precise alignment of optical components is crucial. Some photodiodes, essential for measuring the laser signal, for example, become ineffective at low temperatures, making the sensor blind. We had to adjust the composition of the semiconductors to maintain sensitivity at 20K.”
What is the impact of this research?
“My research can improve the sensitivity of future detectors like the Einstein Telescope by reducing the thermal and seismic noise that limits measurements at low frequencies. The cryogenic sensors I am developing make it possible to monitor the efficiency of isolation systems and reduce unwanted vibrations. These advances could also be applied in other fields, such as cryogenic quantum computers, for example. It’s so exciting!”
