Showing papers on "Winding number published in 1979"
IBM1
TL;DR: The following general relations involving force, momentum and topological winding number of a translating magnetic domain are derived from the Landau-Lifshifz equation in a context appropriate to bubbles: the gyrotropic force tending to deflect a steadily moving domain is proportional to a mean winding number linear in Bloch point coordinates as discussed by the authors.
28 citations
TL;DR: In this article, the instanton in the nonlinear two-dimensional < or = model is interpreted as a tunneling process through a potential barrier between two vacuums, and it is shown that the sigma-model vacuum is still unique by demonstrating that two such vacusums may also be connected by processes that carry zero winding number and which do not require tunneling through a barrier.
Abstract: We study the instanton in the nonlinear two-dimensional < or = model and show that it can be interpreted, in Minkowski space, as a tunneling process through a potential barrier between two vacuums. In this case the process carries nontrivial winding number. We then show, using this interpretation, that the sigma-model vacuum is nevertheless unique by demonstrating that two such vacuums may also be connected by processes that carry zero winding number and which do not require tunneling through a barrier. Some geometrical aspects of instanton solutions are also given.
3 citations