Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Journal of Physics A Mathematical and General

Critical couplings of mixed spin-1/2-spin-S Ising model: a free-fermion approximation

K -F Tang

Published Nov 21, 1988• 36 citations
Publisher

Abstract

A free-fermion approximation procedure is applied to the mixed spin-1/2-spin-S Ising models. The author's results for the critical coupling K c are in very satisfactory agreement with the high-temperature series results of Yousif and Bowers (1984).
DOI
10.1088/0305-4470/21/22/010

Related papers

High-temperature series expansion studies of mixed spin-1/2-spin-S Ising models

B Y Yousif, Roger Bowers

Mixed spin Ising models have less translations symmetry than their 'single spin' counterparts and are well adapted for the study of a certain type of ferromagnetism. In this articles the high-temperature series expansion work of Schofield and Bowers (1981)-who studied mixed spin- 1 / 2 -spin-1 Ising models-is generalised by replacing the spin-1 objects by arbitrary spin-S ones. The new series are used to investigate the spin dependence or independence of critical parameters in a novel setting. There is no evidence to suggest that the exponents studied are spin dependent.

Journal of Physics A Mathematical and General•Dec 1, 1984•42 citations

High-temperature series expansions for mixed spin-S-spin-S' Ising models

G J A Hunter, R. C. Ll. Jenkins, Chris J. Tinsley

Describes the development of high-temperature series expansions for general mixed spin-S-spin-S' Ising models on simple loose-packed lattices. It extends previous work on the simpler special case S'=1/2. Coefficients of the series for the initial susceptibility and specific heat of these models on the square, SC and BCC lattices are presented. A preliminary analysis of the results for the particular case S=1, S'=3/2 is given, and the critical ratio K c and the susceptibility exponent gamma are estimated.

Journal of Physics A Mathematical and General•Oct 21, 1990•25 citations

The Critical Points of a Generalized Mixed Spin Model with Free Fermion Approximation

Fu-Gao Wang, Wen-yan Jia, Jia-Zhen Hu

A generalized mixed spin model with anisotropic interactions is considered on the union jack lattice. We find that the model is equivalent to a free fermion model. The critical temperature is obtained. In special cases, we get the same results as exact solutions.

Communications in Theoretical Physics•Sep 15, 1994•1 citation

High-temperature series expansion analyses of mixed-spin Ising model

S. L. Schofield, Roger Bowers

A high-temperature series expansion in the cumulant form of Brout (1959, 1960) is applied to mixed-spin Ising models on simple quadratic, simple cubic and body-centred cubic lattices. Motivation is provided primarily by an investigation of critical phenomena in Ising models with less than the usual translational symmetry and of relevance to the study of ferrimagnetism. Secondary motivation, appropriate to the simple quadratic lattice, is derived from a desire to obtain results that can be compared with those of renormalisation-group calculations performed elsewhere by the authors. Series expansions of the susceptibility and specific heat are obtained to seventh and tenth order, respectively. The derived expansion coefficients are analysed through both ratio and Pade approximant methods and exponent values are found to be in good agreement with those suggested by the universality hypothesis.

Journal of Physics A Mathematical and General•Aug 1, 1981•25 citations

Critical temperatures of the spin- s Ising model

Theodore W. Burkhardt, Robert H. Swendsen

Critical temperatures of the spin-$s$ Ising model with nearest-neighbor interactions are calculated with an approach based on Kadanoff's lower-bound renormalization transformation. An initial transformation converts the spin-$s$ Hamiltonian into a spin-1/2 Hamiltonian, which is then analyzed with a spin-1/2 renormalization transformation. The calculation is performed for the $d=2$ square lattice and the $d=3$ bcc lattice. For comparison the critical temperatures are also estimated from the ten-term high-temperature series for the susceptibility given by Camp and Van Dyke. The agreement is very good.

Physical review. B, Solid state•Apr 1, 1976•38 citations

Spin-1 and mixed-spin Ising model in a transverse field

Song-Tao Dai, Qing Jiang, Zhen‐Ya Li

Transverse Ising models with spin 1 and mixed spins are studied by use of the discretized path-integral representation and the two-spin cluster approximation. The free energy and the critical transverse field of the systems are obtained.

Physical review. B, Condensed matter•Aug 1, 1990•15 citations
Mixed spin Ising models have less translations symmetry than their 'single spin' counterparts and are well adapted for the study of a certain type of ferromagnetism. In this articles the high-temperature series expansion work of Schofield and Bowers (1981)-who studied mixed spin- 1 / 2 -spin-1 Ising models-is generalised by replacing the spin-1 objects by arbitrary spin-S ones. The new series are used to investigate the spin dependence or independence of critical parameters in a novel setting. There is no evidence to suggest that the exponents studied are spin dependent.
Describes the development of high-temperature series expansions for general mixed spin-S-spin-S' Ising models on simple loose-packed lattices. It extends previous work on the simpler special case S'=1/2. Coefficients of the series for the initial susceptibility and specific heat of these models on the square, SC and BCC lattices are presented. A preliminary analysis of the results for the particular case S=1, S'=3/2 is given, and the critical ratio K c and the susceptibility exponent gamma are estimated.
A high-temperature series expansion in the cumulant form of Brout (1959, 1960) is applied to mixed-spin Ising models on simple quadratic, simple cubic and body-centred cubic lattices. Motivation is provided primarily by an investigation of critical phenomena in Ising models with less than the usual translational symmetry and of relevance to the study of ferrimagnetism. Secondary motivation, appropriate to the simple quadratic lattice, is derived from a desire to obtain results that can be compared with those of renormalisation-group calculations performed elsewhere by the authors. Series expansions of the susceptibility and specific heat are obtained to seventh and tenth order, respectively. The derived expansion coefficients are analysed through both ratio and Pade approximant methods and exponent values are found to be in good agreement with those suggested by the universality hypothesis.
Critical temperatures of the spin-sss Ising model with nearest-neighbor interactions are calculated with an approach based on Kadanoff's lower-bound renormalization transformation. An initial transformation converts the spin-sss Hamiltonian into a spin-1/2 Hamiltonian, which is then analyzed with a spin-1/2 renormalization transformation. The calculation is performed for the d=2d=2d=2 square lattice and the d=3d=3d=3 bcc lattice. For comparison the critical temperatures are also estimated from the ten-term high-temperature series for the susceptibility given by Camp and Van Dyke. The agreement is very good.