Dynamics of stripe patterns in type-I superconductors subject to a rotating field

The evolution of stripe patterns in type-I superconductors subject to a rotating in-plane magnetic field is investigated magneto-optically. The experimental results reveal a very rich and interesting behavior of the patterns. For small rotation angles, a small parallel displacement of the main part of the stripes and a corotation of their very ends are observed. For larger angles, small sideward protrusions develop, which then generate a zigzag instability, ultimately leading to a breaking of stripes into smaller segments. The short segments then start to corotate with the applied field although they lag behind by approximately 10°. Very interestingly, if the rotation is continued, reconnection of segments into longer stripes also takes place. These observations demonstrate the importance of pinning in type-I superconductors. © 2005 The American Physical Society.