Zigzag phase transition in the frustrated Ising honeycomb lattice
Paulo Fernando Dias, M. Schmidt
Abstract
We investigate the thermal phase transitions of the ${J}_{1}\text{\ensuremath{-}}{J}_{2}\text{\ensuremath{-}}{J}_{3}$ Ising model on the honeycomb lattice. This model exhibits the zigzag (ZZ) antiferromagnetic phase, which is observed in the Ising honeycomb compound ${\mathrm{FePS}}_{3}$. By employing a cluster mean-field approach, we describe the role of exchange couplings on phase transitions and thermodynamics of the model. We found first- and second-order transitions between ZZ and paramagnetic phases. Moreover, the model hosts thermal order-by-disorder state selection and, for weak third-neighbor couplings, signatures of strong frustration, such as a round maximum in the specific heat. Our results provide a picture for the nature of thermally driven phase transitions in a wide range of exchange interactions. We show that the first-order phase transition observed in ${\mathrm{FePS}}_{3}$ is hosted by the present microscopic model by adopting exchange couplings from literature.