Key Points
- China’s SHMFF resistive magnet set a new world record by producing a magnetic field of 42.02 tesla, surpassing the previous record of 41.4 tesla.
- SHMFF’s hybrid magnet, which combines resistive and superconducting elements, previously set a record of 45.22 tesla in 2022.
- High magnetic fields allow researchers to discover new physical phenomena and improve measurement accuracy in sensitive experiments.
- Resistive magnets consume a lot of power—32.3 megawatts in this case—but they offer flexibility by quickly ramping up magnetic fields.
China has claimed the world’s most powerful resistive magnet title, achieving a magnetic field over 800,000 times stronger than Earth’s natural field. On September 22, the magnet at the Steady High Magnetic Field Facility (SHMFF) at the Hefei Institutes of Physical Science within the Chinese Academy of Sciences produced a steady magnetic field of 42.02 tesla. This new record narrowly surpasses the previous mark of 41.4 tesla, set in 2017 by the US National High Magnetic Field Laboratory (NHMFL) in Florida.
Resistive magnets, such as the one in China, are made from coiled metal wires and are widely used globally in research facilities. This record-setting magnet represents China’s continued push to develop magnets that sustain stronger magnetic fields. According to Joachim Wosnitza, a physicist at the Dresden High Magnetic Field Laboratory in Germany, such advances will enable scientists to explore new frontiers in physics.
This latest breakthrough follows another major achievement in 2022 when SHMFF’s hybrid magnet, which combines resistive and superconducting magnets, reached a magnetic field of 45.22 tesla, making it the world’s most powerful steady-state magnet.
High-field magnets are crucial in scientific research, particularly in studying advanced materials like superconductors, which carry electric current without heat loss at low temperatures. According to Marc-Henri Julien, a condensed-matter physicist in France, these high magnetic fields allow researchers to observe new physical phenomena and manipulate states of matter that would remain hidden.
Additionally, they enable more precise measurements in sensitive experiments, making it easier to detect faint signals, notes Alexander Eaton, a physicist at the University of Cambridge. Guangli Kuang, a physicist at SHMFF, explained that achieving this latest record took years of refining the magnet’s design, underscoring the task’s difficulty.
While resistive magnets have been around longer than hybrid or fully superconducting ones, they can maintain high magnetic fields for extended periods, making them valuable for experiments. Unlike newer magnets, resistive magnets can ramp up their fields much faster, providing greater experimental flexibility, says Wosnitza. However, their power consumption is immense. For example, the SHMFF’s resistive magnet required 32.3 megawatts of electricity to set the record, making these magnets costly to operate.
Researchers are focusing on developing more energy-efficient hybrid and superconducting magnets to address this. In 2019, NHMFL researchers demonstrated a small superconducting magnet that briefly reached 45.5 tesla. SHMFF is currently working on a 55 tesla hybrid magnet, which would consume less energy. However, building these new magnets presents challenges, including higher construction costs and the need for complex cooling systems.
