Skyrmion physics beyond the lowest Landau-level approximation
نویسندگان
چکیده
The effects of Landau-level mixing and finite thickness of the two-dimensional electron gas on the relative stability of Skyrmion and single spin-flip excitations at Landau-level filling factor n51 have been investigated. Landau-level mixing is studied by fixed-phase diffusion Monte Carlo, and finite thickness is included by modifying the effective Coulomb interaction. Both Landau-level mixing and finite thickness lower Skyrmion excitation energies and favor Skyrmions with fewer spin flips. However, the two effects do not work ‘‘coherently.’’ When finite thickness is included, the effect of Landau-level mixing is strongly suppressed. @S0163-1829~99!52136-X#
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