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.

Researchers have demonstrated a new way to make spatially separated lasers synchronize and act as a single coherent light source—without extreme conditions or complex materials.

A team of physicists from the University of Southampton (UK), University of Warsaw (PL), Military University of Technology (PL), Institut Pascal, Université Clermont Auvergne, CNRS (FR), and CNR (IT) has developed a new class of tunable photonic devices in which multiple tiny laser beams spontaneously synchronize and behave as a unified, spatially extended and coherent light source. Remarkably, this effect is achieved at room temperature using a simple system based on liquid crystals and organic dye molecules, opening new possibilities for low-cost and reconfigurable optical technologies.

The work is published in the journal Nature Communications. The study demonstrates that spatially separated laser spots inside an optical microcavity can spontaneously phase-lock—that is, align (or synchronize) their oscillations—and form a collective state known as a “supermode.” Traditionally, such behavior has been observed only in highly specialized semiconductor systems operating at cryogenic temperatures and in the so-called strong light-matter coupling regime.