Where We're Going...

A lot of you have probably been thinking, “OK, world, this is the future. Where is my flying car?”

"I need something more... stylish."

Well, before you get your proverbial panties in a bunch, think about how that would work. Without involving jets (which are dangerous for a commercial vehicle) and propellers (which would make your car a plane) the only thing left to make your car fly would be the power of magnetism. Everyone’s pushed a magnet across a table before; in theory, a strong enough magnet would be able to push off a metal surface and, with, a motor in it, possibly drive itself around. However, that magnet you pushed does flips, skids, and is just entirely unstable if pushed from the bottom. How could one implement your fantastic new magnet technology in a stable car, one that wouldn’t flip over when you turned it on? The answer: superconducting levitation. Believe it or not, that is a real phrase, and the technology is being implemented as we speak.

Superconductors are defined as any material that has zero resistance when placed in an electric current or magnetic field. Surprisingly, superconductors don’t really have any special properties at room temperature. They’re not magnetic; they don’t really carry a charge; they really just look like a chunk of rock. The magic happens when you lower that same chunk of rock below its superconducting critical temperature. The critical temperature of most superconductors is really freakin’ cold: the highest transition temperatures are still under 100 Kelvin, or -183° Celsius. However, when this temperature is hit, the superconductive material takes on some very unique properties.

First of all, the superconductor is now super-magnetic; get a magnet near it, and it will shoot around, just like a piece of iron. This newfound magnetism is called the Meissner Effect, and allows the next step to occur. If you forcefully push the magnet down onto the superconductor, getting it almost close enough to touch, the superconductor starts to become trapped in the magnetic field of the magnet. Because a superconductor has no resistance, the magnetic field can just keep going through it forever. The flux trapping effect is so strong that, when you take your hand away from the magnet, you’re left with something quite amazing:

That is a floating magnet, sir.

That’s right: the magnet is floating in place. You can spin it, make it wobble, do whatever you want; the magnet won’t really move from that spot because of the flux trapping effect. There are other ways to fix a magnet in place, for sure, but those all use electricity, while a super-cooled superconductor just uses its own unique properties. This makes its potential as a source of levitation intriguing at the very least, and promising at the most. 

That being said, all of the technologies you might be familiar with that involve floating magnets, like Maglev trains and floating globes, implement electromagnetic levitation and not the super-cooled Meissner effect. Maglev trains do have superconducting components, though, that give the engineers greater control and accuracy over the functions of the train. While a superconductor may not be able to power much, it can make it easier to power everything else.

And besides: magical hovering magnets. Enough said.

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Bonus: Young physicists and floating magnets. They think science is cool! Adorable.

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