Spin‐one Ising model with biquadratic exchange interaction within functional integration method
O. Vatamaniuk, Yu. K. Rudavskii
Abstract A spin‐one Ising model with biquadratic exchange interaction is investigated within a functional integration approach. The phase diagram is analyzed by means of Landau's free energy expansion. The dependence of the features of the system on the ratio of bilinear to biquadratic exchange interaction constants is discussed. In the random phase approximation, expressions for phase transition temperatures and the tricritical point for the ferromagnetic transition are obtained.
physica status solidi (b)•Sep 1, 1996•9 citations