Thermodynamical behavior of the Blume-Capel model in the vicinity of its tricritical point

Abstract: We investigate the thermodynamic properties of the zero-field Blume-Capel model in the vicinity of its tricritical point (TCP). We calculate the quadrupole moment, internal energy, and entropy densities employing an exact numerical recursion procedure for the model defined on a hierarchical lattice of fractal dimension $d$. We explore the scaling behavior of the isothermal quadrupolar susceptibility and, the isothermal and constant crystal-field specific heat as a function of the temperature and the reduced crystal-field parameter along the ferromagnetic and the \emph{ordered paramagnetic} phase frontier. Results achieved for systems with dimensions $d=2$ and $3$ exhibit the main features of the continuous and first-order transitions in the TCP neighborhoods. We also probe the phase coexistence in the $\lambda$-diagram and the latent heat in the vicinity of the tricritical point locus.