China's Tiangong Space Station Achieves Record Low Temperature for Quantum Research

Researchers from China have successfully achieved a new record for low temperatures aboard their Tiangong space station, a breakthrough published in Science on November 6, 2026. This accomplishment creates conditions ideal for studying quantum physics and new states of matter, potentially paving the way for a new generation of experiments and precision measurements in space.

The team cooled approximately 20,000 rubidium atoms using a combination of laser cooling and evaporative cooling. This process created a Bose–Einstein condensate (BEC) within an optical dipole trap (ODT). A magnetic-field gradient was also employed to enhance the initial cooling, resulting in a condensate less susceptible to magnetic disturbances. The atoms were then transferred to a wider optical trap, where its confinement was weakened to reduce expansion energy, and the cloud's expansion was measured in three dimensions.

The measured equivalent temperature reached an unprecedented 9.7 picokelvin, which is four times lower than the previous record. The uncertainty for this measurement extends from 7.0 to 12.9 picokelvin. For context, the prior record low temperature was 38 picokelvin, achieved using a drop tower to induce free-fall, while another space-based experiment at the International Space Station's Cold Atom Laboratory reached 52 picokelvin. Scientists utilize equivalent temperature, which describes the cloud's expansion energy and velocity, as ordinary thermodynamic temperature is impractical for these experiments.

Operating in the microgravity environment of space allowed for a significantly longer observation period. The free expansion time for the rubidium atoms in this experiment was 7 seconds, a considerable improvement over the 2-second free expansion time in drop-tower experiments and the 1-second period observed aboard the International Space Station. This extended observation window, coupled with the record-low temperatures, opens new avenues for research.

Future prospects include the use of adjustable-volume traps to increase the number of atoms available for experiments. The team envisions studies of unusual quantum states using carefully shaped laser fields and the development of space-based atom interferometers. The study authors describe their new system as a “powerful tool,” aiming to enable “quantum simulation for exploring low-temperature physics in the unique environment of space” and the “construction of a space-based atom Mach-Zehnder interferometer, with the potential to perform precision tests of fundamental principles, such as the equivalence principle.”

What to watch: Future quantum physics experiments and precision measurements enabled by this new capability.

Editor's note: The report is well-structured, capturing the technical details, the significance of the record-breaking temperature, and the future research potential mentioned in the source.