Zero temperature solutions of the Edwards-Anderson model in random Husimi Lattices

TL;DR

This paper analyzes the zero-temperature solutions of the Edwards-Anderson model on Husimi lattices, revealing how loop size parity influences the solution space structure and phase transitions.

Contribution

It provides a detailed analytical and numerical study of the model's solution space, stability, and phase transitions on Husimi lattices with different loop sizes.

Findings

Odd loop Husimi lattices have a stable paramagnetic solution at T=0.

Even loop Husimi lattices lack this trivial paramagnetic solution.

Identified phase transitions from paramagnetic to spin glass and from spin glass to ferromagnetic.

Abstract

We solve the Edwards-Anderson model (EA) in different Husimi lattices. We show that, at T=0, the structure of the solution space depends on the parity of the loop sizes. Husimi lattices with odd loop sizes have always a trivial paramagnetic solution stable under 1RSB perturbations while, in Husimi lattices with even loop sizes, this solution is absent. The range of stability under 1RSB perturbations of this and other RS solutions is computed analytically (when possible) or numerically. We compute the free-energy, the complexity and the ground state energy of different Husimi lattices at the level of the 1RSB approximation. We also show, when the fraction of ferromagnetic couplings increases, the existence, first, of a discontinuous transition from a paramagnetic to a spin glass phase and latter of a continuous transition from a spin glass to a ferromagnetic phase.