The low-temperature phase of the Heisenberg antiferromagnet in a fermionic representation

Azakov S., Dilaver M., Oztas A. M.

INTERNATIONAL JOURNAL OF MODERN PHYSICS B, vol.14, no.1, pp.13-28, 2000 (SCI-Expanded) identifier


Thermal properties of the ordered phase of the spin-1/2 isotropic Heisenberg Antiferromagnet on a d-dimensional hypercubical lattice are studied within the fermionic representation when the constraint of a single occupancy condition is taken into account by the method suggested by Popov and Fedotov. Using a saddle point approximation in the path integral approach we discuss not only the leading order but also the fluctuations around the saddle point at one-loop level. The Influence of taking into account the single occupancy condition is discussed at all steps.