The power of magnetic levitation-Part 1

A device developed in laboratories at Cornell demonstrates that useful applications of superconducting ceramics are already at hand. The device is a high-speed superconducting bearing that operates by magnetically levitating a rotor. Speeds up to 120,000 revolutions per minute have been achieved without the need for feedback control, and the prospects are good for reaching a million rpm in vacuum. By comparison, currently available magnetic bearings allow speeds of more than 100,000 rpm in a vacuum, but require complex feedback circuits to maintain stability