Magnetic behavior of a ferro-ferrimagnetic ternary alloy AB\(_\rho\)C\(_{1-\rho}\) with a selective site disorder: the case study of a mixed-spin Ising model on a honeycomb lattice

• Published in: arXiv.org
• Main Authors: Torrico, Jordana, Strečka, Jozef, Rojas, Onofre, Martins de Souza, Sergio, Marcelo Leite Lyra
• Format: Paper
• Language: English
• Published: Ithaca Cornell University Library, arXiv.org 04.02.2020
• Subjects: Anisotropy; Compensation; Critical temperature; Ferrimagnetism; Ising model; Magnetic properties; Magnetization; Phase transitions; Temperature dependence; Ternary alloys; Transition temperature
• DOI: 10.48550/arxiv.2002.01572

Phase transitions, compensation phenomenon and magnetization of a ferro-ferrimagnetic ternary alloy AB\(_{\rho}\)C\(_{1-\rho}\) composed of three different kinds of magnetic ions A, B and C with the spin magnitude 1/2, 1 and 3/2 are examined within the framework of a mixed-spin Ising model on a honeycomb lattice with a selective annealed site disorder on one of its two sublattices. It is supposed that the first sublattice of a bipartite honeycomb lattice is formed by the spin-1/2 magnetic ions, while the sites of the second sublattice are randomly occupied either by the spin-1 magnetic ions with a probability \(\rho\) or the spin-3/2 magnetic ions with a probability \(1-\rho\), both being subject to a uniaxial single-ion anisotropy. The model under investigation can be exactly mapped into an effective spin-1/2 Ising model on a triangular lattice through the generalized star-triangle transformation. For a specific concentration of the spin-1 (spin-3/2) magnetic ions, it is shown that the ferro-ferrimagnetic version of the studied model may display a compensation temperature at which the total magnetization vanishes below a critical temperature. The critical temperature strikingly may also become independent of the concentration of the randomly mixed spin-1 and spin-3/2 magnetic ions for a specific value of a uniaxial single-ion anisotropy. The spontaneous magnetic order may be notably restored at finite temperatures through the order-by-disorder mechanism above a disordered ground state, which results in an anomalous temperature dependence of the total magnetization with double reentrant phase transitions.