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Researchers at the University of Tokyo set a new record when they created the strongest controllable indoor magnetic field ever – and subsequently blew up their lab in the process. Both incredible events may have happened in less time than it takes for you to blink your eye, but the entire thing was caught on camera for our repeated viewing pleasure.
The generator was built in a specially designed lab produced to test its material properties, which uses a method known as electromagnetic flux compression. The team was expecting the magnetic field to peak at around 700 Teslas (the standard unit for measuring magnetic field strength, not Elon’s), but wound up at around 1,200. That means it's some 400 times higher than the fields generated by the powerful magnets used in MRI machines and about 50 million times stronger than the Earth’s own magnetic field. As Motherboard points out, a fridge magnet has a strength of just 0.01 Tesla.
Let’s be clear here: It’s not the largest magnetic field ever produced. In 2001, Russian researchers created a magnetic field using explosives that reached 2,800 Teslas, which was so strong and uncontrollable it also blew up their equipment, but it couldn’t be tamed.
The megagauss generator just before it’s switched on. Some parts for the device are exceedingly rare and very few companies around the world are capable of producing them. ©2018 Shojiro Takeyama/University of Tokyo
Physicists with the university say their (mostly) controllable indoor magnetic field will further our understanding of how to reach the “quantum limit” necessary for nuclear fusion, a theoretical power generator that uses nuclear energy to produce heat for electricity in a bid for clean energy.
“With magnetic fields above 1,000 Teslas, you open up some interesting possibilities,” said UTokyo physicist Shojiro Takeyama in a statement. “You can observe the motion of electrons outside the material environments they are normally within. So we can study them in a whole new light and explore new kinds of electronic devices. This research could also be useful to those working on fusion power generation.”
Lasting thousands of times longer than any of the world’s strongest magnetic fields, UTokyo’s magnetic field was so quick, it lasted just one-thousandth of a blink of an eye, yet it was sustained longer than any other attempt with similar strength, which is also promising.
“One way to produce fusion power is to confine plasma – a sea of charged particles – in a large ring called a tokamak in order to extract energy from it,” explained Takeyama of the results published in the Review of Scientific Instruments. “This requires a strong magnetic field in the order of thousands of teslas for a duration of several microseconds. This is tantalizingly similar to what our device can produce.”
Earth’s own magnetic field is 25 to 65 microteslas. The megagauss generator system creates a field of 1,200 teslas, about 20 million to 50 million times stronger. ©2018 Shojiro Takeyama/University of Tokyo
