Fans of Star Trek, The Jetsons or Phil of the Future, rejoice. Everyone else, prepare to have your mind blown. Researchers from Tel Aviv University have harnessed a scientific phenomenon that is very reminiscent of a hover car: quantum levitation.
They coat a wafer of sapphire with a super-thin (as in 1 micrometer thick) layer of yttrium barium copper oxide (a type of ceramic). Then they turn it into a super conductor by cooling the puck with liquid nitrogen, down to negative 301 degrees Fahrenheit, which, amazingly makes it the warmest effective super conductor around. Super conductors have a few properties that are useful for quantum levitation.
They have very little electrical resistance (which means electrons can move around in them freely) and can carry electric currents for very long periods while losing minimal energy to heat or friction. Usually, once a material has transitioned to the super conducting state, magnetic fields cannot go through it (that’s called the Meissner Effect). However, due to the thinness of this puck, little tiny bits of magnetic field do go through, creating what are called “flux tubes.” In the flux tubes, superconductivity disappears.
When something is a super conductor, it is very diamagnetic, meaning if a magnetic force is applied to it externally, it will create an equal and opposite magnetic force. Watch this video and look for the “locking” effect. This effect is a combination of the equal and opposite magnetic fields created by the disk, and the super conductor’s effort to keep the flux tubes pinned down so they cannot move around and destroy more of the superconductivity. These two properties allow the disk to be oriented at any angle, and hold that position above the magnets.
Quantum levitation is already used in real life, particularly in MagLev trains. However, researchers have said that the extreme cold requirement for super conductivity is among a few hurdles science needs to address before any hovercrafts will be hitting stores.
In the meantime, I share the sentiment of Christopher from thisiscolossal.com: “Excuse me while I clean fragments of my brain off my monitor. If somebody had shown me this in grade school I would be a physicist now.”
Holly Domke is a student in the College of Engineering. She can be reached at firstname.lastname@example.org. The Missing Link: Weird Science appears on appears on Fridays.