International. Physicists at the University of Bremen, Germany, have produced the lowest temperature ever recorded, 38 PicoKelvin, which is 38 trillionths of a degree above absolute zero.
Absolute zero is measured as -273.15°C and is the lowest possible temperature on the thermodynamic scale. It is impossible for an object to actually reach this temperature because there would have to be atomic motion or zero kinetic energy in its atoms. A team of physicists from the Center for Microgravity and Applied Space Technology (ZARM) at the University of Bremen in Germany has come very close to absolute zero.
While investigating the wave properties of atoms, the team caught a cloud of gas composed of rubidium atoms in a magnetic field in a vacuum chamber. This cloud of gas then cooled until it became a Bose-Einstein condensate (BEC), a phenomenon in which atoms begin to act essentially as a large atom, allowing strange quantum effects to become visible to the naked eye.
The researchers then dropped the BEC 120 meters down the ZARM drop tower. During the fall, they also turned on and off the magnetic field containing the gas cloud several times. Switching slows down the expansion of the gas to almost a complete stop, greatly reducing its temperature due to the reduced molecular velocity.
The researchers were only able to maintain the record temperature for two seconds. According to their simulations, this temperature could be maintained for about 17 seconds in a weightless environment like the International Space Station.
Source: New Atlas.