We're getting closer and closer to absolute zero. A multi-organization team of researchers from Germany and France set a new record for the coldest temperature ever recorded in a lab, a press statement explains.
The temperature record, set at 38 picokelvins, or 38 trillionths of a degree warmer than absolute zero, could have wide-ranging implications for the field of particle physics.
That's because some materials exhibit increasingly unusual behavior the closer they get to absolute zero, which is equal to -459.67 °F (-273.15 °C), and is commonly measured as 0 Kelvins. The liquid form of helium, for example, becomes a "superfluid," meaning it flows freely regardless of friction.
The research, published in the journal Physical Review Letters, details how researchers at the University of Bremen's Center for Applied Space Technology and Microgravity used a time-domain matter-wave lens system, which is a lens made out of quantum gas.
Temperature record holders want to get even colder
The experiment took place in the Bremen Drop Tower's 122-meter-high drop tube. They created a rubidium gas cloud at the top of the tower and held it in place using magnets that also served to turn the atoms in the cloud into a Bose-Einstein condensate, making it extremely cold. When the gas cloud was released from its magnetic trap, it fell down the drop tube at the same time as expanding in all directions, making it even colder.
Though the whole process only lasted two seconds, detectors in the Bremen Drop Tower were able to measure the kinetic energy of the atoms, allowing the researchers to calculate the temperature of 38 picokelvins.
Experiments conducted in the International Space Station's Cold Atom Lab have reached temperatures as cold as 100 nanoKelvin, or 100 millionths of a degree above absolute zero, but the new experiment has provided a new breakthrough. The researchers have also stated that, by reducing the number of atoms in the cloud before it is released, they might be able to get even closer to absolute zero. They also say their setup could be used to test theories of gravity at the quantum level, providing a new window into the mysterious world of quantum mechanics.