Effects of competing interactions on phase transition temperature in the Ising model
DOI:
https://doi.org/10.54939/1859-1043.j.mst.111.2026.95-103Keywords:
Disordered Ising model; Doped manganese perovskites; Effective field theory; Phase diagram.Abstract
This paper focuses on studying the influence of competitive interaction on the phase diagram in a disordered Ising model using the effective field method. The competitive interaction factor is controlled by two parameters, the competition probability p and the fluctuation D. We obtain a phase diagram divided into three distinct regions according to critical temperatures. Specifically, in the range 1 < D < 1.005 and D > 1.4, the system exhibits a single phase transition from ferromagnetic to paramagnetic states. In the range 1.005 ≤ D ≤ 1.4, two critical points tc1 and tc2 are formed corresponding to the AF – FM – PM phase transition sequence. Simultaneously, we observe that the shift of the phase transition temperature depends on the two model parameters (p, D), similar to the effect of doping concentration on the phase transition temperature in the doped manganese perovskites.
References
[1]. E. Dagotto et al., “Colossal magnetoresistant materials: The key role of phase separation”, Physics Reports, Vol. 344, pp. 1-153, (2001).
[2]. N. Chau et al., “Spin glass-like state, charge ordering, phase diagram and positive entropy change in Nd0.5-xPrxSr 0.5MnO3 perovskites”, Journal of Magnetism and Magnetic Materials, Vol. 303, pp. e402-e405, (2006).
[3]. G. Lalitha et al., “Magnetocaloric behavior of chromium doped Pr0.5Sr0.5MnO3 system”, Physica B: Condensed Matter, Vol. 571, pp. 101-104, (2019).
[4]. R.K. Dokala et al., “Irreversible metamagnetic transitions in Yb3+ distorted tetragonal Pr0.45Sr0.55MnO3”, Journal of Physics D: Applied Physics, Vol. 57, p. 045001, (2024).
[5]. Giang H. Bach et al., “First Order Magnetization Process in Polycrystalline Perovskite Manganite”, Materials Transactions, Vol. 56, No. 9, pp. 1320-1322, (2015).
[6]. Oanh K.T. Nguyen et al., “Fluctuation inducing fractional magnetization behavior on the Shastry–Sutherland lattice”, Physica B: Condensed Matter, Vol. 583, p. 412012, (2020).
[7]. P. H. Nguyen at al., “Effective field theory investigation for a disordered Ising model in the description of amorphous magnetic systems”, Journal of Non-Crystalline Solids, Vol. 643, p. 123165, (2024).
[8]. H.B. Callen, “A note on Green functions and the Ising model”, Physics Letters, Vol. 4, Issue 3, p. 161, (1963).
[9]. B.T. Cong et al., “Theory of a disordered spin lattice”, J. of Magnetism and Magnetic Materials, Vol. 140-144, Part 1, pp. 259-260, (1995).
[10]. T.A. Ho et al., “Critical behavior and magnetocaloric effect of Pr1 −xCaxMnO3”, J. of Applied Physics, Vol. 117, p. 17D122, (2015).
[11]. G. Lalitha et al., “Magnetocaloric behavior of chromium doped Pr0.5Sr0.5MnO3 system”, Physica B: Condensed Matter, Vol. 571, pp. 101-104, (2019).
[12]. Jieyang Fang et al., “Study on the structural transition and inverse magnetocaloric effect of Dy-substituted Pr0.5Sr0.5MnO3”, Materials Chemistry and Physics, Vol. 323, p. 129626, (2024).
