Geometric anti-spring works near absolute zero, suppressing vibrations below 0.185 hertz
09/07/2026
Close-up photo of the instrument. Credit: Leiden University
Physicists and instrument makers in Leiden have succeeded in optimizing a spring that almost completely filters out vibrations at temperatures near absolute zero. This breakthrough opens the door to a new generation of highly sensitive experiments. The research is published in the journal Measurement Science and Technology.
"Our new special spring reduces the disruptive vibrations down to 0.185 hertz, which is a major improvement," says Ph.D. candidate Louw Feenstra. Instrument makers Kees van Oosten and Hugo van Bohemen designed and built the new instrument in their workshop and tested it in the lab together with Feenstra.
Today, many—if not all—modern physics experiments are based on extremely precise measurements. Such measurements are often carried out inside a cryostat, a device that cools materials to temperatures as close as possible to absolute zero (0 Kelvin equals -273.15°C). Until now, cryostats had one major drawback: Their cooling systems generate strong vibrations, particularly around 1 hertz—roughly one vibration per second. For sensitive experiments, this can seriously affect the results.
Inspired by gravitational wave research
"Our design—a geometric anti-spring—was inspired by techniques used in gravitational wave research," van Oosten explains. "The collaboration with Alberto Bertolini from Nikhef really allowed us to hit the ground running. Our instrument is based on a special, extremely 'soft' suspension system that works at low temperatures without the need for a structure several meters in size."
Precision engineering at the micrometer scale
"Building such a system turned out to be an enormous technical challenge," van Bohemen says. "Each of the springs had to be adjusted with a precision of just a few tens of micrometers, while the entire system also had to operate reliably at extremely low temperatures."
"This project simply would not have been possible without the combining of expertise and excellent collaboration," says physicist Milan Allan.
Toward quieter quantum experiments
The researchers see many potential applications for their new setup: ultra-stable microscopes, quantum experiments and future gravitational-wave detectors. In addition, there are opportunities to further improve the design. While the current system primarily suppresses vertical vibrations, future versions will also aim to reduce vibrations in the horizontal direction.
For now, however, the most important milestone has been achieved: proof that a geometric anti-spring can also function in a cryogenic environment. This brings a new generation of ultra-quiet experiments one step closer.
Source https://tinyurl.com/3jxdhsna via Phys.org
