A model ferromagnet with first and second order phase transitions

doi:10.1016/0375-9601(74)90089-9

Physics Letters A

Volume 47, Issue 1, 25 February 1974, Pages 23-24

https://doi.org/10.1016/0375-9601(74)90089-9 Get rights and content

Abstract

A model ferromagnet with pair and four spin interaction strengths in the ratio x is shown to have classical behaviour for x > 3, and discontinuous magnetization for x ⪕ 3, the point x = 3 corresponding to a tricritical point.

References (7)

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There are more references available in the full text version of this article.

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A Husimi rhombus lattice with random angles to present the configurational stochasticity in exact thermodynamic calculation
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The first reason is that, it is a classical system that has been thoroughly studied for many years [12–15], we can easily compare and validate the calculation to previous studies. Secondly, since this is an exactly solvable thermodynamic model [11,16–21], the thermal fluctuation indicated by the exact calculation imprints the point of stochasticity in an exactly-solvable deterministic system, which we would like to address in this work, i.e. the calculation still follows a deterministic way but it gives out randomness in the real system. And another significance of applying Ising spins on this random lattice, is that we can combine the idea of spin system and structural glass model to investigate the off-crystal metastable state.
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A cluster analysis optimization technique for partitioning data is applied to a class of distributions which are functions of a single variable. It is shown that under certain realizable conditions an infinitesimal change in the data distribution causes a large, abrupt change in the location of the optimal boundary separating two data clusters. This abrupt (phase) transition is illustrated with an example.
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A model ferromagnet with first and second order phase transitions

Abstract

Anns. Phys.

Phys. Rev.

J. Phys.