Transient backbending behavior in the Ising model with fixed magnetization

Abstract

The physical origin of the backbendings in the equations of state of finite but not necessarily small systems is studied in the Ising model with fixed magnetization (IMFM) by means of the topological properties of the observable distributions and the analysis of the largest cluster with increasing lattice size. Looking at the convexity anomalies of the IMFM thermodynamic potential, it is shown that the order of the transition at the thermodynamic limit can be recognized in finite systems independently of the lattice size. General statistical mechanics arguments and analytical calculations suggest that the backbending in the caloric curve is a transient behaviour which should not converge to a plateau in the thermodynamic limit, while the first order transition is signalled by a discontinuity in other observables.

24 pages, 11 figures

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Cited by in corpus (11)

• Role of isospin in the nuclear liquid-gas phase transition
• Distribution of the largest fragment in the Lattice Gas Model
• Isoscaling as a measure of Symmetry Energy in the Lattice Gas Model
• Critical adsorption and critical Casimir forces in the canonical ensemble
• Statistical field theory with constraints: application to critical Casimir forces in the canonical ensemble
• Looking for bimodal distributions in multi-fragmentation reactions
• Ising analogue to compact-star matter
• Fluctuations of fragment observables
• Dynamical and statistical bimodality in nuclear fragmentation
• Finite size effects on the phase diagram of the thermodynamical cluster model
• Thermodynamics of compact-star matter within an ising approach