Levitation Experiments Using the Meissner Effect

Abstract

The phenomenon that a superconductor levitates above a magnet is called the Meissner effect. Because the superconducting state repels the magnetic field of magnets, superconductors can levitate above magnets. The Meissner effect experiments require superconductors, magnets and LN₂. The magnetic field distribution of the magnet needs to be understood to conduct a superconducting levitation experiment. The distribution of magnetic field on the single magnet is similar to a water fountain with a maximum point in the centre. It is thus difficult to levitate the superconductor above a single magnet. Of course, if the size of the magnet is quite large, the shape of the magnetic field is almost flat, so superconductors can be levitated above it. However, due to the limitation of magnetization capacity, it is difficult to manufacture magnets of several tens of centimetres or more. For this reason, we made the magnetic levitation platforms by connecting several magnets. In this chapter, we demonstrated a variety of Meissner effect experiments using the magnetic platforms.