China sets world record in steady high magnetic field research

Chinese scientists recently produced a steady field of 452,200 gauss, or 45.22 Tesla, beating the previous world record set nearly 23 years ago to become the highest steady magnetic field by a working magnet in the world.

Scientific staff adjust the Steady High Magnetic Field Facility at the High Magnetic Field Laboratory, Chinese Academy of Sciences, Heifei, east China's Anhui province. [People's Daily Online/Xu Minhao]

The new world record occurred at the hybrid magnet of the Steady High Magnetic Field Facility (SHMFF) in Hefei, east China's Anhui province, indicating China's ability to provide firm support for scientists' exploration of the physical world.

A solenoid can produce a magnetic field when an electric current passes through it - the higher the current, the stronger the magnetic field. That's how the hybrid magnet of the SHMFF was designed.

However, larger electric currents would also lead to a surging electromagnetic force upon the conductor, hence extraordinarily increasing the heat of the hybrid magnet. Therefore, precise, stable and advanced materials and processing techniques are needed to generate a stronger magnetic field that's steady and controllable.

The Earth's magnetic field is about 0.5 gauss, which is able to make the magnetized needle of any compass in the world point to the south. The record-breaking steady field generated by China's SHMFF this time, which stands at 452,000 gauss, is 900,000 times stronger than the Earth's magnetic field.

The steady high magnetic field creates extreme experimental conditions for the study of physical science and contributes to major scientific discoveries. It helps scientists find new physical phenomena and laws of matter.

Widely applied in physics, chemistry, material science, life science and engineering, the high magnetic field is a tool for crossover studies of science, engineering and technologies. It is also hailed as a cradle for Nobel Prizes.

There are currently five major labs of steady high magnetic fields around the world located in the U.S., France, the Netherlands, Japan and China.

In 2016, the Chinese team produced a steady field of 40 Tesla, five Tesla lower than the 45-Tesla world record created by the U.S. in 1999.

This time, though the new record set by China is only 0.22 Tesla higher than the previous record, the progress was made with incredibly huge efforts.

Ye Zhaohui, academician of the Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences (CAS), compared the progress to how 100-meter dash performance is improved.

"At present, the world record of (men's) 100-meter dash is 9.58 seconds, but it's still not clear whether this is the fastest humans can run. To run even 0.01 second faster than the record is incredibly difficult," he said.

In 2016, the research team of the High Magnetic Field Laboratory, Chinese Academy of Sciences produced a steady field of 40 Tesla, the second highest in the world. Photo shows a researcher installing experiment equipment. [People's Daily Online/Xu Minhao]

Similarly, to improve even the tiniest bit on the basis of 45 Tesla calls for huge efforts, including the improvement of materials, technology, techniques and energy supply, as well as innovation in research and design methods, Ye told People's Daily.

According to him, it took five years for Chinese scientists to set the new record, during which they made over 10 technological revolutions and solved a number of problems, making major technical breakthroughs.

The new record has laid a solid foundation for the establishment of an opto-magnetic facility, another major science facility planned by the CAS High Magnetic Field Laboratory.

Kuang Guangli, academic director of the laboratory introduced that the opto-magnetic facility will include a series of magnet devices with the world's highest steady-state magnetic field represented by 55-Tesla hybrid magnets and 36-Tesla superconductive magnets, as well as advanced wave sources such as microwave and visible light.

It will be used to build a batch of opto-magnetic measurement systems in high magnetic fields that aim to solve bottlenecks of major national needs in the development of new electronic materials, research and application of high-temperature superconductivity mechanisms, new medicine development and manufacturing of special materials.