CHAOTIC LEVITATED MOTION OF A MAGNET SUPPORTED BY SUPERCONDUCTOR

The forced vertical vibration of a magnet supported by a high temperat ure superconductor, YBa2Cu3O7, is shown to produce anomalous dynamics, which are quasi-periodic, period doubling, and chaotic oscillations. They are believed to be caused by the nonlinear hysteretic force betwe en the magnet and the superconductor. The system has two routes to cha os. One is the route from quasi-periodic oscillations to chaos and ano ther the route from period doubling oscillation to chaos. The experime ntally observed features of both bifurcations to chaotic oscillations are compared to the numerical solutions of a hysteretic force model.