LEGOs are often used by scientists in conducting experiments, and just this week, physicists at Lancaster University wanted to see how these popular bricks react to the lowest temperature possible. 

CRYOGENIC REFRIGERATORS

The researchers made this experiment possible by using a dilution refrigerator that is able to cool objects to temperatures close to absolute zero. In a video released by the physicists, Professor George Pickett explained the methodology in which the dilution refrigerator can expose objects to temperatures as low as the thousandth of a degree above absolute zero. 

So what happened to the LEGO brick and Minifigure? It survived unscratched from the experiment. The physicists behind this experiment published the findings in Nature. In a press release issued by Lancaster University, the physicists described that LEGO bricks are able to provide better thermal isolation than other bulk insulator materials and are able to maintain its structural integrity. The practicality of these results suggests that relatively cheaper bricks made from Acrylonitrile Butadiene Styrene materials can be used as an affordable alternative to be used as a thermal insulator. 

According to Dr. Dmitry Zmeev, the results of these findings are significant in the sense that the physicists were able to discover that the clamping arrangement between LEGO blocks is responsible for LEGO structures to behave as an extremely good thermal insulator. 

Physicists are developing a more advanced structure made from Acrylonitrile Butadiene Styrene materials that can be designed using 3D printers and eventually be used as thermal insulators for the next generation of dilution refrigerators.

HOW DILUTION REFRIGERATORS WORK?

Cryogenics is the science that deals with low temperatures, and ever since its invention 50 years ago, the dilution refrigerator continues to be relevant and at the center of the global multi-billion dollar industry. Dilution refrigerators are important to modern experimental physics and engineering, especially in the development of quantum computers.

Dilution refrigerators use helium and its two isotopes (helium-3 and helium-4) for its cooling capacity. Helium can condense into a liquid as it reaches a very low temperature (4.2 Kelvin or -269 degrees Celsius or -452 degrees Fahrenheit), and this makes it a very valuable cryogen. The evaporation and condensation cycle of dilution refrigerators are similar to the cycle found in a commercial refrigerator, but unlike commercial refrigerators, the dilution fridge cools down temperatures down to 1.5 Kelvin or -271 Celsius. Dilution refrigerators are a key component of the Cryogenic Dark Matter Search experiment where commercial dilution refrigerators are used to cool specialized Ge detectors down to 50 milliKelvin to directly detect dark matter which astronomers believe to be a fundamental component of the universe.

The usage of Acrylonitrile Butadiene Styrene, such as LEGO instead of the current solid materials used in the industry, means the production of thermal insulators can be significantly cheaper. The researchers behind this study proposed that the next step to this production is to design and print a new thermal insulator using a 3D printer, and these will be used for the next generation of dilution refrigerators.