According to experts, a hybrid magnet in China has recently surpassed the
previous record for the most potent steady magnetic field.
A magnet that took years to produce at the stable High Magnetic Field
Facility (SHMFF) of the Chinese Academy of Sciences has a stable magnetic field of 45.22
tesla, which is thousands of times stronger than the typical souvenir fridge
magnet.
The National High Magnetic Field Laboratory (MagLab) in the US had held the
record for a constant magnetic field of 45 tesla since 1999, but this beats
it. The discovery expands the parameters frequently used to examine
different physical processes, opening up new avenues for investigation and
invention.
The research teams at MagLab and SHMFF have each been developing their own
hybrid magnets for a while. An outer superconducting ring and an inside
resistive Bitter magnet (a magnet made of stacked plates) are used to create
the magnetic field in this magnet. Each of these technologies has its own
limitations: the Bitter magnet needs significantly more power input while
the superconducting magnet has a maximum magnetic field strength.
These restrictions are considerably lessened by combining the two
technologies, enabling the spread of a strong, continuous magnetic field.
This is how the SHMFF achieved a stable magnetic field strength of 40 tesla
in 2016—a remarkable accomplishment in and of itself—and how MagLab created
their 45 tesla magnet.
The Chinese Academy of Sciences team, however, was not pleased to stop
there and has continued to work on its magnet ever since. That effort has at
last paid off.
According to
physicist Guangli Kuang, academic head of the High Magnetic Field Laboratory of Hefei Institutes
of Physical Science, Chinese Academy of Sciences, "to achieve [a] higher
magnetic field, we innovated the structure of the magnet, and developed new
materials." The production of the Bitter CDs was improved as well.
The team was able to reach their 45.22 tesla record with a power input of
26.9 megawatts; once again, the magnet seems to be a leader. MagLab needs to
supply 30 megawatts of electricity to its 45 tesla magnet.
The SHMFF magnet, according to the team, is a development in materials
science.
The National Steady State High Magnetic Field Experiment Facility's hybrid
magnet, according to the team's statement on the High Magnetic Field
Laboratory website, "produces the highest steady state magnetic field in the
world, effectively improving the experimental conditions for scientists to
conduct material science research and will play an indispensable key role in
the research of low-power electronic materials and other fields."
The hybrid magnet's openness, sharing, and user service levels will all
significantly improve as the magnetic field's intensity grows.
In the meanwhile, MagLab continues to hold the record for the strongest
magnetic field ever created on Earth: in a test run in 2019, a
superconducting magnet temporarily reached a strength of 45.5 tesla. We'll
watch to see whether further advancements cause it to formally overtake the
lead.
