Artigo
Heisenberg model on a space with negative curvature: Topological spin textures on the pseudosphere
Autor
Belo, L. R. A.
Oliveira Neto, N. M.
Moura Melo, W. A.
Pereira, A. R.
Ercolessi, Elisa
Institución
Resumen
Heisenberg-like spins lying on the pseudosphere (a 2-dimensional infinite space with constant negative curvature) cannot give rise to stable soliton solutions. Only fractional solutions can be stabilized on this surface provided that at least a hole is incorporated. We also address the issue of ‘in-plane’ vortices, in the XY regime. Interestingly, the energy of a single vortex no longer blows up as the excitation spreads to infinity. This yields a non-confining potential between a vortex and an antivortex at large distances so that the pair may dissociate at arbitrarily low temperature.