Super Strong Magnet Blows the Door Off a Laboratory

In a secure room at the University of Tokyo's Institute for Solid State Physics in Kashiwa, Chiba, near Tokyo, an electromagnet, when powered with an electrical current, generates a magnetic field capable of blowing open the heavy doors of the facility. This magnet has already created one of the most powerful magnetic fields on Earth and it only keeps getting stronger. In 2018, the magnetic field reached a strength of 1,200 teslas, a record for an indoor pulsed field (for reference, typical clinical MRI scanners run at only 1.5 to 3 teslas).

How Is a Magnet Like This Created?

The team in Tokyo was able to achieve that massive level of power by pumping 3.2 megajoules of energy into a small electromagnetic coil. The inner lining of that coil, a thin metal cylinder called a liner, is driven inward by electromagnetic force and implodes at about Mach 15, or more than 3 miles per second (5 km/s). When it collapses, the magnetic field created inside of the coil gets squeezed until its force reaches a strength impossible to reach with conventional magnets. As soon as that happens, the coil will collapse fully, destroying itself entirely.

Shojiro Takeyama, a physicist at the University of Tokyo and lead author of the study believes that the device can reach strengths of 1,800 teslas if their team can apply 5 megajoules rather than the previous 3.2. However, because the device destroys itself each time, the team must clean up and repair the room after every shot.

But Why?

Why would we need a magnet that strong? Takeyama says that the purpose of the experiments is to observe the motion of electrons outside the material environments they are normally in. Their team will put different materials into the magnet to learn how those electrons will behave under extreme conditions. Studying those moments of extreme magnetism before the coil’s self-destruction should reveal properties of electrons normally invisible to science.

The main issue with magnetic fields this powerful is that they almost always self-destruct within moments of their birth. So much energy is exerted on the device generating it that at least some part of the device fails.

In the future, magnets like this could become commonplace and might be more manageable but until then, we’ll need to invest in some stronger doors on our laboratories.

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