Random field effects on the phase diagrams of spin-1/2 Ising model on a honeycomb lattice

TL;DR

This study investigates how different types of quenched random magnetic fields influence the phase diagrams, magnetization, and energy of the spin-1/2 Ising model on a honeycomb lattice, revealing complex behaviors like reentrant phases.

Contribution

It introduces an effective field approximation that accounts for spin correlations, providing new insights into the effects of various random field distributions on phase transitions.

Findings

Random field distribution shape affects phase diagrams and magnetization.

Reentrant behavior and tricritical points are identified under certain conditions.

The effective field approximation captures correlations between spins.

Abstract

Ising model with quenched random magnetic fields is examined for single Gaussian, bimodal and double Gaussian random field distributions by introducing an effective field approximation that takes into account the correlations between different spins that emerge when expanding the identities. Random field distribution shape dependence of the phase diagrams, magnetization and internal energy is investigated for a honeycomb lattice with a coordination number q=3. The conditions for the occurrence of reentrant behavior and tricritical points on the system are also discussed in detail.