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arXiv · 2307.06193

Purely antiferromagnetic frustrated Heisenberg model in spin ladder compound BaFe$_2$Se$_3$

Roll A.·Petit S.·Forget A.·Colson D.·Banerjee A.·Foury-Leylekian P.·Balédent V
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Abstract

The spin dynamics in the block magnetic phase of the iron-based ladder compound \bfs\ has been studied by means of single crystal inelastic neutron scattering. Using linear spin wave theory and Monte-Carlo simulations, our analysis points to a magnetic Heisenberg model with effective frustrated antiferromagnetic couplings only, able to describe both the exotic block order and its dynamics. This new and purely antiferromagnetic picture offers a fruitful perspective to describe multiferroic properties but also understand the origin of the stripe-like magnetic instability observed under pressure as well as in other parent compounds with similar crystalline structure.

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Roll A., Petit S., Forget A., Colson D., Banerjee A., Foury-Leylekian P., Balédent V. 2023-07-12. Purely antiferromagnetic frustrated Heisenberg model in spin ladder compound BaFe$_2$Se$_3$. https://doi.org/10.1103/physrevb.108.014416

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