The Meissner Effect, Quantum Levitation

Tel-Aviv University shows the phenomenon of “Quantum Levitation“ using a track around which a superconductor can float. Superconductivity and magnetic fields are like oil and water, they don’t mix. When it can, the superconductor will push out any magnetic fields from the interior in a process called; the Meissner effect. It happens when a sample is cooled below its superconducting transition temperature, where it then cancels out its magnetic flux.

Because of electromagnetic induction (where an electric current is created when a conductor is moved through a magnetic field), a perfect conductor won’t change the magnetic flux when it cruises through at zero resistance. However, when cooled to the superconductor state the magnetic flux is expelled. Now we have perfect diamagnetism – where the interior magnetic field nears zero. At this point, if an external magnetic field is introduced, it will create an opposing magnetic field.
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.
Superconductivity and magnetic field do not like each other. When possible, the superconductor will expel all the magnetic field from inside. This is the Meissner effect. In our case, since the superconductor is extremely thin, the magnetic field DOES penetrates. However, it does that in discrete quantities (this is quantum physics after all! ) called flux tubes.

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.
Superconductivity and magnetic field do not like each other. When possible, the superconductor will expel all the magnetic field from inside. This is the Meissner effect. In our case, since the superconductor is extremely thin, the magnetic field DOES penetrates. However, it does that in discrete quantities (this is quantum physics after all! ) called flux tubes.