Skyrmions in quantum Hall systems with realistic force laws

We study the charged excitations of quantum Hall systems at integer filling fractions v = 2n + 1, for a force law that takes account of the non-zero thickness of the electron gas. We show that for values of the thickness that are typical of standard experimental devices, when the Zeeman energy is sufficiently small, the 'skyrmion' excitations have lower energies than quasiparticle excitations not only at v = 1 but also at several higher filling fractions. Results are presented for the energies and spins of the low-energy charged excitations as functions of the Zeeman energy. (C) 1997 Elsevier Science B.V. All rights reserved.