Topology and interactions in domain structures of garnet films: Imaging by Scanning Hall Susceptometry.
Abstract
Pattern formation and topological defect interactions have been investigated in domain structures of ferrimagnetic yttrium-iron garnet film. We visualize interaction between the topological defects in a branching pattern of magnetic domains by scanning a.c. susceptometry technique. Dilative strain created by an applied external magnetic field drives a gradual transformation from a disordered "labyrinthine" to an ordered stripe configuration. In the course of this transformation unbound disclinations in the pattern are found to mutually interact over distances that are much larger than a stripe period; interactions are confined within narrow lines connecting defects of the opposite topological sign. We investigate role of the boundary conditions, local gradients and kinetic effects for the formation of metastable disordered states. Results are compared with experimental evidence obtained by other imaging techniques and with existing theories of defect unbinding in similar condensed matter systems.
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 2003
- Bibcode:
- 2003APS..MARV30003M