Development of a cryo-cooled superconducting magnet with a large magnetic-force field

In order to study magnetic levitation easily, we develop a cryo-cooled large magnetic field gradient superconducting magnet as the insert magnet for a large bore (220 mm cylindrical room temperature bore) cryo-cooled superconducting magnet. The insert magnet consists of a modified cusp coil and generates large magnetic field gradient. Combined with the background magnet, this magnet system realizes the stable magnetic levitation for the diamagnetic materials. The magnet system is designed to generate 1400 T ²/m for the magnetic levitation of water. As a result, this cryo-cooled magnet system quenched from the insert magnet, but could achieve nearly 1050 T ²/m. As a performance test, a bismuth tip was levitated using the newly developed cryo-cooled superconducting magnet.