Gap decay in superconducting magnetic bearings under the influence of vibrations

One of the most obvious applications of high-T-c superconductors is in the construction of magnetic bearings. We have been examining the effect that vibrations will have on the stability of such devices. Concern has been expressed about the effect of flux creep on such devices but recently we have identified that vibrations may also have a significant effect. In experiments we have determined that under certain circumstances the bearing gap may decay. This decay can be either positive or negative, that is the bearing gap may decrease or increase; this occurs over and above any effects which might be expected from thermally activated flux creep. We propose a simple model based on a spring damper system which may be used to predict when decay will occur.