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It sounds like magic, but it actually is an astonishing phenomena captured by Tel-Aviv University. Watch the video below, then stick around for the science.


Here’s an even better video representation of the effect:


Amazing right?

So what is going on here? What we are witnessing in these videos is called the Meissner effect. Once a material has transitioned into the superconducting state (you have to cool materials down to near absolute zero or -273 degrees Celsius) it will eject all of the magnetic field lines from the interior of the superconductor. This ejection of the magnetic field is what “locks” the superconductor in place. It looks something like this:

In the case of the video above, Tel Aviv University used the following:

We start with a single crystal sapphire wafer and coat it with a thin (~1µm thick) ceramic material called yttrium barium copper oxide (YBa2Cu3O7-x ). The ceramic layer has no interesting magnetic or electrical properties at room temperature. However, when cooled below -185ºC (-301ºF) the material becomes a superconductor. It conducts electricity without resistance, with no energy loss. Zero.

To get a little more technical, the magnetic field lines, as seen the above photo, only penetrate the superconductor in the “weak” areas, or the boundaries between the grains of the material. These “flux tubes”, or areas where the magnetic field is passing through the material, destroy the superconducting properties in the surrounding area. Therefore, to maintain superconductivity, the superconductor “tries” to keep these tubes in one place (the weak areas), and does not allow them to move. Because the flux tubes would move if the superconductor moved in any spatial direction, the superconductor stays “locked” in space. This is why the experimenter can move the superconductor and the resulting position becomes locked.

Yeah, science is cool like that.

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