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Monte Carlo study of the classical antiferromagnetic $J_1$-$J_2$-$J_3$ Heisenberg model on a simple cubic lattice

A. N. Ignatenko, S. V. Streltsov, V. Yu. Irkhin

TL;DR

This work investigates the thermodynamics of the classical $J_1$-$J_2$-$J_3$ Heisenberg model on a simple cubic lattice to understand frustration-driven phase behavior. It employs extensive Monte Carlo simulations with a heat-bath algorithm and Binder cumulant analysis, comparing results to mean-field and Tyablikov approximations across broad exchange ratios. A key finding is a minimum in the Neel temperature at $J_2^{(c)}=J_3+1/4$, with the frustration ratio $f=|\theta|/T_N$ increasing with $J_3$; Binder analysis reveals both second- and first-order transitions depending on the ordering wave vector, and a critical-like $ u$ for certain regimes. The results highlight the crucial role of fluctuations in frustrated magnets and bear relevance to antiferromagnetic perovskites such as CaMnO$_3$ and HgMnO$_3$, informing interpretation of experimental thermodynamics and guiding theoretical approaches beyond mean-field theory.

Abstract

An extensive Monte Carlo study of the classical Heisenberg model on a simple cubic lattice with antiferromagnetic exchange interactions $J_n$ between the first, second, and third neighbors is performed in a broad region of $J_2 / J_1$, $J_3 / J_1$ ratios, and temperature. The character of the phase transitions is analyzed via the Binder cumulant method. The Neel temperature $T_{\mathrm{N}}$ and the frustration parameter (the ratio $f= |θ|/T_{\mathrm{N}}$, $θ$ being the Curie-Weiss temperature) are calculated. A comparison with the Tyablikov approximation is carried out. The strength of the frustration effects is explored. Possible applications to antiferromagnetic perovskites, such as CaMnO$_3$ and HgMnO$_3$, are discussed.

Monte Carlo study of the classical antiferromagnetic $J_1$-$J_2$-$J_3$ Heisenberg model on a simple cubic lattice

TL;DR

This work investigates the thermodynamics of the classical -- Heisenberg model on a simple cubic lattice to understand frustration-driven phase behavior. It employs extensive Monte Carlo simulations with a heat-bath algorithm and Binder cumulant analysis, comparing results to mean-field and Tyablikov approximations across broad exchange ratios. A key finding is a minimum in the Neel temperature at , with the frustration ratio increasing with ; Binder analysis reveals both second- and first-order transitions depending on the ordering wave vector, and a critical-like for certain regimes. The results highlight the crucial role of fluctuations in frustrated magnets and bear relevance to antiferromagnetic perovskites such as CaMnO and HgMnO, informing interpretation of experimental thermodynamics and guiding theoretical approaches beyond mean-field theory.

Abstract

An extensive Monte Carlo study of the classical Heisenberg model on a simple cubic lattice with antiferromagnetic exchange interactions between the first, second, and third neighbors is performed in a broad region of , ratios, and temperature. The character of the phase transitions is analyzed via the Binder cumulant method. The Neel temperature and the frustration parameter (the ratio , being the Curie-Weiss temperature) are calculated. A comparison with the Tyablikov approximation is carried out. The strength of the frustration effects is explored. Possible applications to antiferromagnetic perovskites, such as CaMnO and HgMnO, are discussed.
Paper Structure (7 sections, 12 equations, 9 figures)

This paper contains 7 sections, 12 equations, 9 figures.

Figures (9)

  • Figure 1: Illustration of the exchange interaction parameters ($J_1, J_2, J_3$) used in the model calculations.
  • Figure 2: Average absolute value of the total $\mathbf{Q}_1$-vector magnetic moment $| \mathbf{M}_{\mathbf{Q}_1} |$ as a function of temperature for $J_2 = 0.391$, $J_3 = 0.05$ and $L = 10$ (left panel); its derivative on temperature (middle panel). Temperature dependence of the specific heat for the same parameters (right panel).
  • Figure 3: The Neel temperature as a function of $J_2$ calculated in the Monte Carlo simulation for $J_3 = 0.05$ and lattice sizes $L = 10$, 20, 30, 40 (empty markers connected with solid lines) and compared with the Tyablikov approximation, $L = \infty$ (bottom dotted line) and the mean field theory (upper dash-dotted line). Arrows point to Neel temperatures for $J_2$ = 0.95 (point A), 0.393 (point B), 0.3 = $J_2^{(\mathrm{c})}$ (point C), and 0.31 (point D).
  • Figure 4: Temperature dependence of the Binder cumulant $U_{\mathbf{Q}_0}$ in the vicinity of the point A ($J_2 = 0.095$, $J_3 = 0.05$) on Fig. \ref{['tn_L10-40']} for different lattice sizes $L$. $T_{\mathrm{cross}}$ = 1.2146. The inset shows $U_{\mathbf{Q}_0}$ as a function of $x = (T/T_{\mathrm{cross}}-1)L^{1/\nu}$ with $\nu=0.7$.
  • Figure 5: Temperature dependence of the Binder cumulant $U_{\mathbf{Q}_1}$ in the vicinity of the point B ($J_2 = 0.393$, $J_3 = 0.05$) on Fig. \ref{['tn_L10-40']} for different lattice sizes $L$. The inset shows the positions of the maximums of $U_{\mathbf{Q}_1}$ as a function of $L$.
  • ...and 4 more figures