Scientists cool Lego blocks to just above absolute zero

British scientists have cooled four stacked Lego blocks to 70 milliKelvin, or slightly above absolute zero. They conclude that the Lego material can be used for numerous cryogenic applications, such as in quantum computing.

The British researchers wanted to measure the thermal conductivity of acrylonitrile-butadiene-styrene, or abs for short, at extremely low temperatures. They placed four Lego bricks, made of abs, on top of each other and placed them in a so-called dilution refrigerator, or a mixing cooling machine. With this they brought the Lego turret to a temperature of 70 milliKelvin. That is converted to -273.08 degrees Celsius, a fraction above absolute zero.

The thermal properties turned out to be so good that the scientists believe that Lego can be used as a cheap alternative to materials such as Macor from Corning and Vespel from DuPont. These materials are used for many applications that require extremely low temperatures.

Not only the Lego material was found to be responsible for the low thermal conductivity, but also the structure of the bricks. “Our results are important because we showed that the way the Lego bricks were attached made the Lego structure behave as a good thermal insulator at cryogenic temperatures,” said Dmitry Zmeev, one of the scientists.

The researchers suspect that self-developed modular material can be made from a 3D printer with even better thermal properties. This could then be used as construction material for mixed cooling machines and for quantum computers, for example.

The researchers published their work in Scientific Reports under the title Lego Block Structures as a Sub-Kelvin Thermal Insulator.