Abstract
The change in the order of the magnetic phase transition in ferromagnetic CoS2 under pressure recently revealed by Goto et al. [Phys. Rev. B56, 14019 (1997)] is explained in terms of an exchange-magnetostriction model that takes into account the magnetoelastic interactions (MEI) of the first and second order with respect to volume deformations. Using numerical values of MEI constants determined from experimental data, the equilibrium and nonequilibrium magnetic phase diagrams have been calculated for CoS2 in the space of variables T (temperature), P (pressure), and H (magnetic field). The temperature dependence of magnetization at various pressures and the magnetization isotherms have been calculated. The results of the calculations show satisfactory agreement with experiment. Analytical expressions for the critical magnetic field and temperature of the first-order magnetic phase transition (FOMPT) and for the FOMPT curve in a magnetic field at a constant pressure have been obtained. The effect of an applied magnetic field on the characteristics of the FOMPT are analyzed.
Similar content being viewed by others
References
T. Goto, Y. Shindo, H. Takahashi, and S. Ogawa, “Magnetic Properties of the Itinerant Metamagnetic System Co(S1−x Sex) under High Fields and High Pressure,” Phys. Rev. B: Condens. Matter 56(21), 14019–14028 (1997).
H. Yamada, “Metamagnetic Transition and Susceptibility Maximum in an Itinerant-Electron System,” Phys. Rev. B: Condens. Matter 47(17), 11211–11219 (1993).
H. Yamada, K. Fukamichi, and T. Goto, “Recent Advances of Itinerant Electron Metamagnetism and Relative Properties of Intermetallic Compounds,” Physica B (Amsterdam) 327(2–4), 148–154 (2003).
N. V. Mushnikov, T. Goto, A. V. Andreev, et al., “Magnetoelasticity of CoS2,” Philos. Mag. B. 80(1), 81–93 (2000).
E. A. Zavadskii and V. I. Val’kov, Magnetic Phase Transitions (Naukova Dumka, Kiev, 1980) [in Russian].
E. Z. Valiev and F. S. Shemet’ev, “Pressure-Induced Tricritical Point and Critical Behavior near the Points of Phase-Diagram Wings in a CoS2 Ferromagnet,” Pis’ma Zh. Eksp. Teor. Fiz. 79(9), 535–538 (2004) [JETP Lett. 79, 427–430 (2004)].
E. Z. Valiev and A. Z. Menshikov, “Linear and Nonlinear Magnetoelastic Interaction in Molecular Field Theory and Invar Anomalies,” J. Magn. Magn. Mater. 46, 199–205 (1984).
I. F. Mirsaev and G. G. Taluts, “On the Theory of First-Order Magnetic Phase Transitions under Conditions of Hydrostatic Pressure: III. Order-Disorder Transitions,” Fiz. Met. Metalloved. 53(2), 251–256 (1982).
G. I. Kataev, “Ferromagnetic Anomaly of Young’s Modulus and Shear Modulus in Invar Alloys,” Fiz. Met. Metalloved. 11(3), 375–381 (1961).
G. Hausch, “Magnetic Exchange Energy Contribution to the Elastic Constants and Its Relation to the Anomalous Elastic Behavior of Invar Alloys,” Phys. Status Solidi A 15, 501–510 (1973).
E. Z. Valiev, “Properties of Ferromagnets with Strong Magnetoelastic Interaction and Invar Anomalies,” Fiz. Met. Metalloved. 49(5), 988–993 (1980).
K. Sato, K. Adachi, T. Okamoto, et al., “Pressure Effect of Curie Point of CoS2 and Ferromagnetic Properties of Co (SxSe1−x )2,” J. Phys. Soc. Jpn. 26, 639–641 (1969).
V. L. Ginzburg, A. P. Levanyuk, and A. A. Sobyanin, “Light Scattering near Phase Transition Points in Solids,” Phys. Rep. (Phys. Lett. C) 57, 153–240 (1980).
R. Griffits, “Proposal for Notation at Tricritical Points,” Phys. Rev. B: Solid State 7, 545–551 (1973).
Yu. A. Izyumov and V. N. Syromyatnikov, Phase Transitions and Crystal Symmetry (Nauka, Moscow, 1984) [in Russian].
L. D. Landau and E. M. Lifshitz, Statistical Physics (Nauka, Moscow, 1976; Pergamon, Oxford, 1980), Part 1.
Author information
Authors and Affiliations
Additional information
Original Russian Text © E.Z. Valiev, F.S. Shemet’ev, 2006, published in Fizika Metallov i Metallovedenie, 2006, Vol. 102, No. 2, pp. 139–146.
Rights and permissions
About this article
Cite this article
Valiev, E.Z., Shemet’ev, F.S. Isotropic magnetoelastic interaction and the pressure-induced first-order magnetic phase transition in CoS2 . Phys. Metals Metallogr. 102, 127–134 (2006). https://doi.org/10.1134/S0031918X06080023
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1134/S0031918X06080023