General topologically invariant microscopical expressions for quantum numbers of particle-like solitons ("skyrmions") are derived for a class of (2+1)D models. Skyrmions are either half-integer spin fermions with odd electric charge or integer spin bosons with even charge. So they cannot be Anderson's spinons or holons. General results are exemplified by a square lattice model reminiscenting high-Tc models.
- Pub Date:
- March 1997
- Condensed Matter - Strongly Correlated Electrons;
- Condensed Matter - Mesoscale and Nanoscale Physics;
- High Energy Physics - Theory
- LaTeX 2.09, 3 pages, no figures. This paper was published in 1989, but cond-mat/9610040 recently brought the subject of the Hopf term into prominence again. The paper is posted "as published", only the citations "to be published" are replaced by the references. Some discussion is dated, but the relations between the Hopf term, the Hall conductivity, the electric charge of the skyrmion, and the topological invariants in the momentum space are valid and relevant