A new record has been set. China has just created a magnetic field 800,000 times more powerful than Earth's using a resistive magnet.
This achievement is the result of years of hard work, led by the team at the Hefei laboratory, a cutting-edge institution in the field.
The 42.02-tesla resistive magnet.
Image CHMFL
On September 22, Chinese researchers produced a constant magnetic field of 42.02 teslas using a resistive magnet. This is a world record. This technology is not just a technical feat: it opens doors to major innovations. A magnetic field of this magnitude allows for the exploration of new phenomena in matter, revealing physical laws that were previously unknown.
Resistive magnets, like the one used for this record, stand out for their ability to generate very powerful magnetic fields, far exceeding those of superconducting magnets. The quick and precise control they offer makes them the tools of choice for researchers.
The Chinese Academy of Sciences, through the CHMFL, is also working on hybrid magnets. These, combining the properties of resistive and superconducting magnets, allow for record-breaking magnetic intensities, such as in 2022 with a field of 45.22 teslas.
But why invest so much in the race for high magnetic fields? The answer is simple: these experimental tools are essential for research in material physics, chemistry, and even biology. More than ten discoveries awarded with Nobel Prizes have been made possible thanks to these magnets.
New world record of stable high magnetic field, 42.02 teslas, using a resistive magnet.
Image CHMFL
Today, scientists are able to manipulate matter in unprecedented ways thanks to these fields. This could lead to major technological advances, such as in metallurgy or the creation of new drugs via magnetic resonance.
This is just the beginning: the teams at Hefei are already planning to develop even more powerful magnets. These new projects could very well transform research in electronics, superconductivity, and the fight against major diseases.
What is a high magnetic field and what types of magnets can generate it?
A high magnetic field is one whose intensity far exceeds that of natural magnetic fields, such as Earth's. It can reach several tens of teslas (the unit of measurement for magnetic fields). These fields allow for the study of rare or inaccessible physical phenomena under normal conditions.
They are generated by different types of magnets: resistive, superconducting, or hybrid. Resistive magnets use large amounts of electrical energy to create a powerful magnetic field, while superconductors utilize materials cooled to extremely low temperatures, allowing them to generate fields without energy loss. Hybrid magnets, on the other hand, combine these two technologies to reach even higher intensities, such as the 45.22 teslas produced in China in 2022.
How does a resistive magnet work?
A resistive magnet is made up of coils of metal wires through which an electric current flows, generating a magnetic field. Unlike superconducting magnets, resistive magnets are cooled with water rather than liquid helium.
The flexibility of resistive magnets lies in their ability to quickly and precisely control the strength of the magnetic field. This characteristic makes them the preferred tool for research requiring frequent and finely tuned magnetic field variations, particularly in the fields of material physics and chemistry.
Why are high magnetic fields essential for scientific discoveries?
High magnetic fields allow scientists to alter the properties of matter in unprecedented ways. By subjecting materials to intense fields, scientists can observe particular behaviors that only manifest under these extreme conditions.
These conditions allow, for example, the exploration of phenomena such as superconductivity, where materials conduct electricity without resistance. They also play a crucial role in discoveries in chemistry and biology, facilitating the understanding of complex molecular reactions and essential biological mechanisms.
Moreover, high magnetic fields are at the heart of medical technologies like nuclear magnetic resonance (NMR), used for diagnostics. By increasing the intensity of the fields, researchers hope to obtain more precise images and molecular information, thus promoting advances in disease treatment and the development of new drugs.
Article author: Cédric DEPOND