Abstract
In this work, the critical temperature of Ising ferromagnetic and anti-ferromagnetic systems in 2 dimensions was extracted via finite-size-scaling analysis on the order parameter calculated from the discrete Fourier transformation. Spin patterns under the effect of thermal fluctuation were generated using Monte Carlo simulation. The discrete Fourier transformation was used to transform spin patterns from spatial domain to wave vector domain, where the order parameter was calculated from this Fourier-harmonics. From the result, it was found that TC = 2.2684 ± 0.0006 J/kB for ferromagnetic system and TC = 2.2689 ± 0.0003 J/kB for anti-ferromagnetic system which match well with the exact theoretical value TC ≈ 2.269 J/kB . As can be seen, the critical temperatures of both systems match well with the exact theoretical values. This study is therefore proposing a fundamental knowledge to extract critical behavior from complicated systems, where the exchange parameter is a periodic function of distance.
Acknowledgment
The authors wish to acknowledge financed support from the Graduate School of Chiang Mai University.