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arXiv · 2407.17878

The incredible diversity of structural and magnetic instabilities in EuTiO3: from paramagnetic to spin glass, spin liquid and antiferromagnetic order

Annette Bussmann-Holder·Reinhard K. Kremer·Efthymios Liarokapis·Krystian Roleder
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Abstract

The perovskite oxide EuTiO3 (ETO) has attracted increased scientific interest due to its potential multiferroic properties and magnetic activity above and below its structural phase transition at TS=282K. Various experiments have indirectly evidenced that this transition is neither a cubic tetragonal nor the only one occurring in ETO. Here, we show new results demonstrating two further instabilities below TS based on lattice dynamics and spin-phonon interactions combined with a Landau free energy model with coupled order parameters. The new transition temperatures perfectly agree with available experimental data where further instabilities have been anticipated.

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Annette Bussmann-Holder, Reinhard K. Kremer, Efthymios Liarokapis, Krystian Roleder. 2024-07-25. The incredible diversity of structural and magnetic instabilities in EuTiO3: from paramagnetic to spin glass, spin liquid and antiferromagnetic order. https://arxiv.org/abs/2407.17878

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