01248nas a2200157 4500008004100000245005900041210005900100300001200159490000800171520080200179100001200981700001600993700001801009700001901027856004401046 1996 eng d00aSkyrme and meron crystals in quantum Hall ferromagnets0 aSkyrme and meron crystals in quantum Hall ferromagnets a154-1570 vT663 aThe ground state of a two-dimensional electron gas at Landau level filling factor n near 1 is studied in the Hartree-Fock approximation. For Zeeman coupling different from zero, the ground state is a Skyrme crystal with both spontaneous long range order in the charge density and spontaneous long range order in the transverse spin density. The energy of the Skyrme crystal is lowest for a square lattice structure with opposing postures for topological excitations on opposite sublattices. We discuss interpretations of our results in terms of non-linear s and generalized spin models for quantum Hall ferromagnets. For zero Zeeman coupling, we find that the ground state can be interpreted as a meron crystal with two interpenetrating sublattices, each supporting quasiparticles with charge e/2.1 aBrey, L1 aFertig, H A1 aCôté, René1 aMacDonald, A H uhttp://stacks.iop.org/1402-4896/T66/154