Magnetic properties of thin film with S = 1. Isothermal susceptibility and magnetic specific heat

The thermodynamic response functions were studied in thin films in the frame of the Blume-Emery-Griffiths model. The method is based on the analysis of the Gibbs free energy and involves calculations of the magnetization and quadrupolar moment distributions. The temperature dependencies of the susceptibility and specific heat are obtained for various biquadratic interaction parameter and non-zero single-ion anisotropy. The behaviour of these functions in different phases: ferromagnetic, paramagnetic and staggered quadrupolar are illustrated in figures and discussed. (author)