Coherent anomaly method for Blume-Capel model

✍ Scribed by K.G. Chakraborty

• Book ID: 103894356
• Publisher: Elsevier Science
• Year: 1992
• Tongue: English
• Weight: 470 KB
• Volume: 189
• Category: Article
• ISSN: 0378-4371
• DOI: 10.1016/0378-4371(92)90138-g

✦ Synopsis

The coherent anomaly method is applied to study the critical exponent for susceptibility X for spin-one Ising model with single-ion anisotropy D. The method used here consists of finding the zeros of the first n polynomials of the power series of the inverse susceptibility )~ and of studying its critical behaviour near the zero point. The inverse series is expressed in powers x = 3Jz/2kT, where J is the nearest neighbour exchange constant, z the number of nearest neighbours, and k the Boltzmann constant. Successive poles x¢c "~ are found to increase as n increases and in the limit n ~ ~ approach the fixed value x*~, which gives the true critical temperature. The effect of single-ion anisotropy (the strength is measured by a = D/Jz) on x~* is studied. The susceptibility )~(xc) is found to be coherently anomalous. The critical data indicate that in addition to scaling singularities one has to consider the correction due to confluent singularities. The magnitude of the correction has been estimated and the results are discussed with reference to those obtained by other authors.