The Faculty of Mathematics and Physics of Charles University, in cooperation with the Czech Academy of Sciences, has launched the most powerful Czech helium liquefier for scientific purposes, with a capacity of 57 liters of liquid helium per hour, which can liquefy up to 70,000 m3 of gaseous helium per year. Scientists will also use the device to re-liquefy extremely volatile rare gases from laboratories, which they recycle in this way.
Thanks to liquid helium, cryogenic laboratories can use superconducting magnets to create strong magnetic fields and temperatures very close to absolute zero, allowing scientists to study the properties of materials under conditions that exist nowhere else in the universe. For example, at CERN, the world's largest low-temperature laboratory, thousands of superconducting magnets are cooled to accelerate particles. Cooling equipment circulating superconducting helium maintains the 23 kilometers of the LHC accelerator at a temperature of -271 °C (1.9 Kelvin).
Cryogenic liquid and gaseous helium is both a tool and a subject of basic research. It is used, for example, to simulate flows inside stars and pulsars, allowing scientists to study phenomena that affect the universe and our world. "Under certain conditions, superfluid helium can flow without internal friction, and its properties can only be explained by quantum mechanics. Quantized vortices and quantum turbulence arise in superfluid helium, phenomena that we have been observing for more than 25 years," explains Professor Ladislav Skrbek, a leading Czech expert in low-temperature physics from the Faculty of Mathematics and Physics at Charles University.
University and academic laboratories using the Troja liquefier achieve similar temperatures for a wide range of experiments, such as cooling superconducting magnets in nuclear magnetic resonance spectrometers. These are used to determine the structure of natural and synthetic compounds, to research the properties of condensed substances and nanoparticles, and for materials research.
"Stable high magnetic fields are essential for materials research. In laboratory conditions, they can only be generated using coils made of superconducting materials, which require liquid helium temperatures to function," said Martin Míšek from the Institute of Physics of the Czech Academy of Sciences.
The new liquefier will supply up to 80,000 liters of liquid helium per year (a significant portion of which will evaporate during handling and transport, be recycled, and liquefied again). Researchers at the MFF UK laboratories consume 20,000 liters, while the second largest consumer, with 16,000 liters, will be the Institute of Physics of the Czech Academy of Sciences. Other academic institutes that will use liquid helium include the Institute of Organic Chemistry and Biochemistry (approx. 3,800 liters), the Institute of Macromolecular Chemistry (800 liters), the Institute of Inorganic Chemistry (400 liters), and the J. Heyrovský Institute of Physical Chemistry (100 liters). Liquid helium is also transported to Prague's Troja from the CEITEC research infrastructure in Brno (3,000 liters).
Helium, the second most abundant element in the universe, has been known since 1868. In the early days, it was also obtained from the pores of uranium minerals from Jáchymov. A fundamental contribution to science was made by Dutch physicist and Nobel Prize winner Heike Kamerlingh Onnes. He first liquefied helium on July 10, 1908, at the University of Leiden, a date considered to be the beginning of modern low-temperature physics.
Source: Press release from the Faculty of Mathematics and Physics, Charles University
Photo: Tomáš Rubín / Faculty of Mathematics and Physics, Charles University
