# Unfolding of phases and multicritical points in the Classical Anisotropic van Hemmen Spin Glass Model with Random Field

## TL;DR

This paper investigates how random fields and interactions in a 3-state spin glass model lead to the emergence of multiple distinct spin glass phases and multicritical points, revealing complex phase behavior.

## Contribution

It introduces a detailed analysis of phase unfolding and multicritical points in a 3-state van Hemmen spin glass model with random fields, highlighting new phase structures.

## Key findings

- Two distinct spin glass phases emerge under strong random fields.
- Four separate phases including a mixed phase are identified.
- Multiple triple and multicritical points are found in the phase diagram.

## Abstract

We study magnetic properties of the 3-state spin ($S_{i}=0$ and $\pm 1$) spin glass (SG) van Hemmen model with ferromagnetic interaction $J_0$ under a random field (RF). The RF follows a bimodal distribution The combined effect of the crystal field $D$ and the special type of on-site random interaction of the van Hemmen model engenders the unfolding of the SG phases for strong enough RF, i. e., instead of one SG phase, we found two SG phases. Moreover, as $J_0$ is finite, there is also the unfolding of the mixed phase (with the SG order parameter and the spontaneous magnetization simultaneously finite) in four distinct phases. The emergence of these new phases separated by first and second order line transitions produces a multiplication of triple and multicritical points.