Journal of the Physical Society of Japan
Susceptibility of Ising Ferromagnet of Restricted Dimensionality
Takuma Ishikawa, Takehiko Oguchi
Abstract
The susceptibility of the restricted-dimensional (one- or two-dimensional-like) Ising model is analyzed by means of the high temperature series expansion. The exchange interaction in a chain (or plane), and inter chains (or planes) are J and λ J , respectively. The first eight terms in the susceptibility series are explicitly obtained. The critical temperature T c and the critical exponent γ are obtained as a function of λ. It is found that the susceptibility shows restricted-dimensional behavior at high temperature ( T ≫ T c ), and shows three-dimensional behavior in the very vicinity of the critical temperature (\(T{\gtrsim}T_{\text{c}}\)) for small λ.