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arXiv · 2306.17015

Evidence for additional third-order transitions in the two-dimensional Ising model

Kedkanok Sitarachu·Michael Bachmann
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Abstract

We employ the microcanonical inflection-point analysis method, developed for the systematic identification and classification of phase transitions in systems of any size, to study the two-dimensional Ising model at various lattice sizes and in the thermodynamic limit. Exact results for the density of states, which were obtained by exact algorithmic computation, provide evidence for higher-order transitions in addition to the well-studied second-order ferromagnetic-paramagnetic phase transition. An independent third-order phase transition is identified in the ferromagnetic phase, whereas another third-order transition resides in the paramagnetic phase. The latter is a dependent transition, i.e., it is inevitably associated with the critical transition, but it remains separate from the critical point in the thermodynamic limit. For a deeper insight into the nature of these additional transitions, a detailed analysis of spin clusters is performed.

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BibTeXRIS

Kedkanok Sitarachu, Michael Bachmann. 2023-06-29. Evidence for additional third-order transitions in the two-dimensional Ising model. https://doi.org/10.1103/physreve.106.014134

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