Non-universal critical behaviour of the two-dimensional Ising model with crossing bonds

✍ Scribed by Kazuhiko Minami; Masuo Suzuki

• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 556 KB
• Volume: 192
• Category: Article
• ISSN: 0378-4371
• DOI: 10.1016/0378-4371(93)90149-x

✦ Synopsis

The two-dimensional square lattice lsing model with the nearest-neighbour ferromagnetic interaction J and the next-nearest-neighbour antiferromagnetic interaction J' is investigated in the interaction range IJ/J'l ~<0.8. This model is shown to violate the ordinary universality hypothesis. Estimations of critical temperature as a function of J/J' by means of an extrapolation method results in the exact critical temperature T~* when IJ/J'[ = 0 and in an approximate T c accurate up to the fourth digit when IJ/J'l is small. The critical exponent 3' is estimated as a function of IJ/J'l with the use of the multi-effective-field theory and the coherent-anomaly method. It is shown, consequently, that y varies continuously as IJ/J' I increases.