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arXiv · 1406.3742

Thermodynamic description of the Ising antiferromagnet on triangular lattice with selective dilution by modified Pair Approximation method

T. Balcerzak·K. Szałowski·M. Jaščur·M. Žukovič·A. Bobák·M. Borovský
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Abstract

The Pair Approximation method is modified in order to describe the systems with geometrical frustration. The Ising antiferromagnet on triangular lattice with selective dilution (Kaya-Berker model) is considered and a self-consistent thermodynamic description of this model is obtained. For this purpose, the Gibbs free-energy as a function of temperature, concentration of magnetic atoms on the selected sublattice, and external magnetic field is derived. In particular, the phase diagram is constructed and a comparison of different methods is presented. The thermodynamic quantities are discussed in the context of their physical validity and the improvement in the description introduced by modified method is emphasized.

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T. Balcerzak, K. Szałowski, M. Jaščur, M. Žukovič, A. Bobák, M. Borovský. 2014-06-14. Thermodynamic description of the Ising antiferromagnet on triangular lattice with selective dilution by modified Pair Approximation method. https://doi.org/10.1103/physreve.89.062140

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