Low temperature static behavior of the two-dimensional quantum easy-axis Heisenberg model

AUTOR(ES)

Leonel, S. A., Pires, A. S. T.

FONTE

Brazilian Journal of Physics

DATA DE PUBLICAÇÃO

2000-06

RESUMO

We use the self-consistent harmonic approximation (SCHA) to study static properties of the two-dimensional quantum Heisenberg model with easy-axis anisotropy. We calculate the critical temperature as a function of the spin value, and compare with classical results. Specifically, we compare how the ratio of critical temperatures varies as a function of the spin S in the quantum and classical cases, for afixed anisotropy parameter. We see that, for values of spin near 5/2, the classical result approximates to the quantum results and the classical calculation is justified. We have also studied the behavior of the magnetization for very small anisotropies. We have shown that our magnetization curves do not present a plateau in the limit of very small anisotropies, as predicted by the real-space renormalization-group calculations.

Documentos Relacionados

• The two-dimensional quantum Heisenberg antiferromagnet with Ising-like anisotropy
• Critical behavior of the spin-3/2 Blume-Capel model on a random two-dimensional lattice
• Two-dimensional life?
• Behavior of several two-dimensional fluid equations in singular scenarios
• A two-dimensional mathematical model of percutaneous drug absorption