Theoretical aspects of magnetic phase transitions in LaMnO3 perovskite

Abstract

This work investigates theoretical aspects of magnetic phase transitions in manganite LaMnO${}_3$. The study focuses on the lattice composed of the sites occupied by the $M{n}^{3+}$ ions, which present antiferromagnetic coupling with coordination number of six. The lattice spins are described by the spin-2 Blume–Capel model and its magnetic and thermodynamic properties are investigated using Mean Field Theory and Effective Field Theory. The behavior of the system is studied as a function of the anisotropic parameter and the external magnetic field, presenting numerical results used to construct magnetization, entropy, magnetocaloric potential and phase diagrams, highlighting regions with first and second order magnetic phase transitions, as well as tricritical and terminal points.