Random, thermodynamic and inverse first order transitions in the Blume-Capel spin-glass

TL;DR

This paper investigates complex phase transitions in a spin-glass model, revealing various types of first-order and inverse transitions, including dynamic and thermodynamic phenomena, using replica symmetry breaking techniques.

Contribution

It provides a detailed analysis of phase transition scenarios in a spin-1 model with p-body interactions, including inverse freezing and multiple transition types, extending understanding of glassy systems.

Findings

Identification of inverse freezing phenomena.

Different transition scenarios including first-order and continuous transitions.

Analysis of static and dynamic transition line inversions.

Abstract

The spherical mean field approximation of a spin-1 model with p-body quenched disordered interaction is investigated. Depending on temperature and chemical potential the system is found in a paramagnetic or in a glassy phase and the transition between these phases can be of different nature. In given conditions inverse freezing occurs. As $p=2$ the glassy phase is replica symmetric and the transition is always continuous in the phase diagram. For $p>2$ the exact solution for the glassy phase is obtained by the one step replica symmetry breaking Ansatz. Different scenarios arise for both the dynamic and the thermodynamic transitions. These include (i) the usual random first order transition (Kauzmann-like) preceded by a dynamic transition, typical of mean-field glasses, (ii) a thermodynamic first order transition with phase coexistence and latent heat and (iii) a regime of inversion of static and dynamic transition lines. In the latter case a thermodynamic stable glassy phase, with zero configurational entropy, is dynamically accessible from the paramagnetic phase. Crossover between different transition regimes are analyzed by means of Replica Symmetry Breaking theory and a detailed study of the complexity and of the stability of the static solution is performed throughout the space of external thermodynamic parameters.