2 papers
cond-mat1995
Spin Waves in Quantum Antiferromagnets
B. Kleine, G. S. Uhrig, E. Müller-Hartmann
Using a self-consistent mean-field theory for the Heisenberg antiferromagnet Krüger and Schuck recently derived an analytic expression for the dispersion. It is exact in on…
cond-mat1995
Ferromagnetism in the Hubbard model: instability of the Nagaoka state on the triangular, honeycomb and kagome lattices
Thoralf Hanisch, Burkhard Kleine, Afra Ritzl +1
In order to analyse the lattice dependence of ferromagnetism in the two-dimensional Hubbard model we investigate the instability of the fully polarized ferromagnetic ground state (…