http://www.youtube.com/watch?v=Ws6AAhTw7RA
The video above is about quantum levitation, the black square one is the high temperature superconductor, in normal temperature it will act like stone, the round shape shiny metal is a powerful magnet.The idea here is that you have a metal at its superconducting state by cooling it down below the critical superconducting temperature (in this case it was cooled down with liquid nitrogen). The result is that the magnet and the superconductor at the same time both attract and repel each other maintaining a fixed distance between them ( caused by the flux trapping effect) . If we turned the magnet to the opposite polarity and then put it neat a superconductor, the superconductor will be shoved away but the superconductor will tend to flip over in order to relaign ifself and then again be atracted by the magnet. You can imagine that we drop the magnet inside a copper (conductor) tube.The fundamental principle of moving magnes inside conductors is that when a magnet moves through a conductor, it wll induce the electric currents and these currents themself have their own magnetic field which will resists the motion that's creating it. The currents that are created will always tend to die away. But in case of superconductor, those currents will not die away. As soon as the currents are induced by introducing the magnets near the superconductor, those currents would remain and keep going even after the magnet has stopped. So if we drop a magnet through a superconductor tube, the magnet will basically be locked and levitating in the tube. The reason why the superconductor levitating above the magnetic filed is that the gravity tries to pull the superconductor down and this will set up the electric current in the superconductor, which have its onw magnetic filed that resist that motion and keep the superconductor floating. The superconductor will always resists the motion by locking itself into to magnetic filed.
Here is another interesting about the superconductor and quantum levitation: http://www.youtube.com/watch?v=Ws6AAhTw7RA
All of this super cool stuff related to conductivity. t's any remarkable phenomenon discovered in 1911 byDutch scientist named Kamerlingh-Onnes. Kamerlingh-Onnes pioneered work at very low temperatures — just a few degrees above the absolute zero of temperature. He succeeded in reaching temperatures much colder than anyone before him, and thus opened a new field of physics that scientist previously unexplored, the field of low temperature physics. The fact is that below an extreme low certain temperature, many metals enter into a new state of matter: the superconducting state.