English

1/N expansion for two-dimensional quantum ferromagnets

Mesoscale and Nanoscale Physics 2009-10-31 v1

Abstract

The magnetization of a two-dimensional ferromagnetic Heisenberg model, which represents a quantum Hall system at filling factor nu=1, is calculated employing a large N Schwinger boson approach. Corrections of order 1/N to the mean field (N=infinity) results for both the SU(N) and the O(N) generalization of the bosonized model are presented. The calculations are discussed in detail and the results are compared with quantum Monte Carlo simulations as well as with recent experiments. The SU(N) model describes both Monte Carlo and experimental data well at low temperatures, whereas the O(N) model is much better at moderate and high temperatures.

Keywords

Cite

@article{arxiv.cond-mat/9801203,
  title  = {1/N expansion for two-dimensional quantum ferromagnets},
  author = {Carsten Timm and S. M. Girvin and Patrik Henelius},
  journal= {arXiv preprint arXiv:cond-mat/9801203},
  year   = {2009}
}

Comments

28 pages, 11 figures included

R2 v1 2026-07-22T12:01:50.269Z