Thermodynamics of a frustrated spin system: Renormalization group approach and scaling

✍ Scribed by Alex H. Lacerda; Adauto J.F. De Souza; F.G. Brady Moreira

• Publisher: Elsevier Science
• Year: 1989
• Tongue: English
• Weight: 760 KB
• Volume: 155
• Category: Article
• ISSN: 0378-4371
• DOI: 10.1016/0378-4371(89)90099-x

✦ Synopsis

We use a real-space renormalization group approach to calculate the thermodynamic properties of the isotropic antiferromagnetic nearest-neighbour Ising model on the triangular lattice.

Our study confirms the important role played by frustration in determining the ground-state properties of the system. In particular, we obtain a finite zero-point entropy and the absence of long-range order. Results for the free energy, the specific heat and the entropy obtained from the first five smallest clusters of a given family, clearly indicate the convergence towards the exact results. We propose a scaling law for the free energy and the temperature, which is used to relate the thermodynamic functions in the finite systems with those in the thermodynamic limit. In such a scaled space the size dependence is almost completely eliminated and the agreement with the exact results is remarkably good for all temperatures.