Topological magnetic solitons in the two-dimensional Mott-Hubbard gap.

Abstract

We derive from first principles the existence of deep level localized electronic gap states, induced by hedgehog solitons, in the two-dimensional Hubbard model. These arise naturally as excitations in a new topological magnetic condensate of the many-electron system associated with π 1 (SO(3)). The condensate exhibits local spin 1/2 magnetic moments as well as topological «spin flux.» This flux emerges microscopically from a homotopically nontrivial phase rotation of the electron spinor field and leads to an intriguing relativistic structure for the Mott-Hubbard gap